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The Agricultural Assessment of Climatic Resource and Modeling in Jianghan Plain-Lake District

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Wuhan University Journal of Natural Sciences 1999年第4期4卷 423-427页

作者： WANG Xue lei 1. WU Yi jin 2, LIU gong hu 1.1. Institute of Geodesy & Geophysics, Chinese Academy of Sciences, Wuhan 430077, China 2. Department of History, University of Wuhan, Wuhan 430077, China Chinese Academy of Sciences Institute of Geodesy &amp Geophysics Wuhan China (GRID:grid.9227.e) (ISNI:***) University of Wuhan Department of History Wuhan China (GRID:grid.49470.3e) (ISNI:***)

The feature of the climatic resource and the agricultural assessment in Jianghan plain lake district are discussed. In order to exploit the climatic resource, we have recommended some three dimensional agriculture development models in this region according to the types of land use, such as paddy field ecological zone, dry land ecological zone, outskirts ecological zone of the city, waterbody ecological zone, woodland ecological zone.

关键词： Jianghan plain climatic resource assessment modeling

耦合混合变量的空间机动飞行器多学科设计优化

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宇航学报 2017年第12期38卷 1253-1262页

作者：粟华王京士龚春林谷良贤李波张孝南陕西省空天飞行器设计重点实验室西安710072 西北工业大学航天学院西安710072 上海卫星工程研究所上海220240

针对复杂耦合下的空间机动飞行器（SMV）多学科设计优化（MDO）问题,开展了同时考虑连续-离散混合变量的MDO求解技术研究。考虑空间机动飞行器总体方案设计需求,建立了包括轨道分系统、电源分系统、结构分系统、推进分系统、GNC分系统... 详细信息

针对复杂耦合下的空间机动飞行器（SMV）多学科设计优化（MDO）问题,开展了同时考虑连续-离散混合变量的MDO求解技术研究。考虑空间机动飞行器总体方案设计需求,建立了包括轨道分系统、电源分系统、结构分系统、推进分系统、GNC分系统等多个学科的空间机动飞行器MDO模型;提出了基于变量转化法的混合变量MDO求解策略,将连续-离散混合变量MDO问题转化为普通MDO问题进行优化求解。优化后的空间机动飞行器总质量相比于初始方案降低了1..1.,证明了本文方法的有效性。与将离散变量作为连续变量优化的直接方式对比分析表明,本文提出的基于变量转化法的混合变量MDO求解策略在求解效率和可靠性方面更优。

关键词：空间机动飞行器多学科设计优化混合变量优化多学科求解策略变量转化法

裂解汽油中噻吩硫在Co-Mo/Al_2O_3上的催化加氢宏观动力学

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燃料化学学报 2005年第5期33卷 576-581页

作者：李建伟李英霞陈标华李成岳张小工北京化工大学可控化学反应科学与技术基础教育部重点实验室北京100029 中国石油兰州石化研究院催化所甘肃兰州730060

采用绝热管式固定床积分反应器,在2.5MPa^3.9MPa、51.K^655K、氢/裂解汽油摩尔比1.8~3.5和裂解汽油中噻吩、单甲基噻吩和双甲基噻吩质量分数为838×1.-6、1.7×1.-6~723×1.-6和1.2×1.-6~723×1.-6下,对Co-Mo/Al2O3催化剂上裂解汽油催... 详细信息

采用绝热管式固定床积分反应器,在2.5MPa^3.9MPa、51.K^655K、氢/裂解汽油摩尔比1.8~3.5和裂解汽油中噻吩、单甲基噻吩和双甲基噻吩质量分数为838×1.-6、1.7×1.-6~723×1.-6和1.2×1.-6~723×1.-6下,对Co-Mo/Al2O3催化剂上裂解汽油催化加氢脱硫的宏观动力学进行了研究。以Powell优化法和Merson迭代法对动力学实验数据进行非线性参数估值,建立了良好吻合实验数据的、裂解汽油催化加氢脱硫的幂函数型宏观动力学模型。噻吩、单甲基噻吩和双甲基噻吩的反应级数分别为0.721.0.735和0.87,对应的加氢反应宏观活化能依次为70.0kJ·mol-1.67.9kJ·mol-1.59.9kJ·mol-1.各噻吩基硫的转化率均随反应压力的提高而增加,3.5MPa以上时,增加的趋势减缓;反应温度的提高有利于噻吩基硫转化率的增加;593K以上时,各硫化物的转化率随温度的增加呈现线性增加的趋势。

关键词：加氢脱硫动力学裂解汽油噻吩基硫

基于有限体积法及FDS格式的感潮河段二维泥沙冲淤模型

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水动力学研究与进展（A辑） 2004年第1期19卷 98-103页

作者：赵棣华沈福新颜志俊卢恭和南京水利科学研究院江苏南京210029 福建水利勘测设计院福州350001

　本文以木兰溪下游裁弯河段为例,建立了有限体积法的水平二维非恒定流均匀沙不平衡输移计算模型。采用黎曼近似解通量差分裂(FDS)格式计算通过各单元边的水流、含沙量法向数值通量,并应用相关的悬移质、推移质河床变形计算公式计算冲... 详细信息

　本文以木兰溪下游裁弯河段为例,建立了有限体积法的水平二维非恒定流均匀沙不平衡输移计算模型。采用黎曼近似解通量差分裂(FDS)格式计算通过各单元边的水流、含沙量法向数值通量,并应用相关的悬移质、推移质河床变形计算公式计算冲淤变化。数值模型经相应的河工模型试验资料率定、检验后,预测了裁弯工程建成后河道可能的冲淤变化,为工程设计和施工提供依据。

关键词：有限体积法黎曼近似解浅水方程无结构网格悬移质推移质含沙量河床变形

Sparse Reconstructive Evidential Clustering for Multi-View Data

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 459-473页

作者： Chaoyu gong Yang You School of Computing National University of SingaporeSingapore

Although many multi-view clustering(MVC) algorithms with acceptable performances have been presented, to the best of our knowledge, nearly all of them need to be fed with the correct number of clusters. In addition, these existing algorithms create only the hard and fuzzy partitions for multi-view objects,which are often located in highly-overlapping areas of multi-view feature space. The adoption of hard and fuzzy partition ignores the ambiguity and uncertainty in the assignment of objects, likely leading to performance degradation. To address these issues, we propose a novel sparse reconstructive multi-view evidential clustering algorithm(SRMVEC). Based on a sparse reconstructive procedure, SRMVEC learns a shared affinity matrix across views, and maps multi-view objects to a 2-dimensional humanreadable chart by calculating 2 newly defined mathematical metrics for each object. From this chart, users can detect the number of clusters and select several objects existing in the dataset as cluster centers. Then, SRMVEC derives a credal partition under the framework of evidence theory, improving the fault tolerance of clustering. Ablation studies show the benefits of adopting the sparse reconstructive procedure and evidence theory. Besides,SRMVEC delivers effectiveness on benchmark datasets by outperforming some state-of-the-art methods.

关键词： Evidence theory multi-view clustering(MVC) optimization sparse reconstruction

Rare earth effects on high temperature oxidation of pure nickel at 1.00 ℃

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Progress in Natural Science:Materials International 2004年第4期 87-90页

作者： JIN Huiming, ZHANG Jianfeng, YAN Kun and gong Zexiang (1. Materials Research Center, Department of Mechanical Engineering, Yangzhou University, Yangzhou 225009, China 2. Department of Materials Science and Engineering, Dalian University of Technology, Dalian 1.001., China) Materials Research Center Department of Mechanical EngineeringYangzhou UniversityYangzhou 225009China Department of Materials Science and Engineering Dalian University of TechnologyDalian 110014China

Isothermal and cyclic oxidation behaviors of pure and yttrium-implanted nickel were studied at 1.00 ℃ in air. SEM and TEM were used to examine the oxide scales formed on nickel substrate. It was found that Y-implantation greatly improved the anti-oxidation ability of nickel both in isothermal and cyclic oxidizing experiments. Acoustic emission (AE) technique was used to study the size and number distribution of defects at the oxide/metal interface. Laser Raman microscopy was also used to study the stress status of oxide scales formed on nickel with and without yttrium. The main reason for the improvement in anti-oxidation and adhesion of oxide scale was that Y-implantation greatly reduced the grain size of NiO and lowered the compressive stress within the scale. In the meantime, Y-implantation inhibited ion diffusion rate in the oxide scale and reduced the size and number of interfacial defects, hence remarkably enhanced the adhesion of protective NiO oxide scale formed on nickel substrate.

关键词： oxidation ion-implantation acoustic emission laser Raman yttrium.

中国南海海绵Luf fariella sp.的次生代谢产物研究

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中国海洋药物 2018年第4期37卷 52-56页

作者：潘增玉康建功程伟潍坊医学院药学院山东潍坊261053 北京大学天然药物及仿生药物国家重点实验室北京100191

目的研究中国南海海绵Luffariellasp.的次生代谢产物及生物活性。方法利用硅胶柱色谱、C1.反相柱色谱,半制备HPLC等方法对海绵提取物进行分离纯化,通过核磁共振、质谱、紫外、红外等波谱学技术,并结合文献理化数据,确定化合物的结构。... 详细信息

目的研究中国南海海绵Luffariellasp.的次生代谢产物及生物活性。方法利用硅胶柱色谱、C1.反相柱色谱,半制备HPLC等方法对海绵提取物进行分离纯化,通过核磁共振、质谱、紫外、红外等波谱学技术,并结合文献理化数据,确定化合物的结构。对分离得到的化合物进行了NF-κB抑制活性评价实验。结果分离鉴定了6个含α、β-不饱和γ–内酯环的二倍半萜类化合物,结构确定为Hippolide H(1.、Hippolide F(2)、Hippolide G(3)、Hippolide E(4)、6Z-neomanoalide(5)、6E-neomanoalide(6)。在NF-κB抑制活性评价实验中,化合物1.4、6具有较好的NF-κB抑制活性。结论南海海绵Luffariellasp.可代谢具有NF-κB抑制活性的二倍半萜类化合物。

关键词： Luffariella sp. 二倍半萜 NF-κB抑制活性评价

Tropical cyclone genesis over the western north Pacific in La Ni?a decay summers: Comparison between 201. and 2021

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Science China Earth Sciences 2024年第10期67卷 3098-3109页

作者： Yunyun LIU Zhensong gong China Meteorological Administration Key Laboratory for Climate Prediction Studies National Climate CentreBeijing 100081China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China

As the primary interannual signal of variability in the tropical ocean-atmosphere interaction, the El Ni?o-Southern Oscillation has a considerable impact on tropical cyclone(TC) activity over the western North Pacific(WNP). Both 201. and2021.were La Ni?a decay years, but TC activity over the WNP during the two summers(June–August) showed notable differences. In 201., summer TC activity was unusually high with a total of 1. TCs, and the region of TC genesis was mainly in the central and eastern WNP. In contrast, only 9 TCs were generated in summer 2021. and the region of TC genesis was primarily in the western WNP. By comparing the characteristics of the large-scale environmental conditions over the regions of TC genesis, the thermal factors of the tropical oceans, and the activity of the Madden-Julian Oscillation(MJO), this study revealed the possible causes for the marked differences in TC genesis over the WNP during the two summers, which both had a similar background of La Ni?a decay. The Indian Ocean Basin Mode(IOBM) transitioned of a cold anomaly in the winter of 201./201.and persisted until summer 201.. At the same time, the Pacific Meridional Mode(PMM) maintained a positive phase, leading to eastward and northward displacement of the Western Pacific Subtropical High in summer, and eastward extension of the tropical monsoon trough, which presented conditions conducive to TC genesis over the Northwest Pacific. Moreover, the days when the MJO stagnated in phases 5 and 6 in the summer of 201. increased by approximately 1.0% relative to climatological state,providing dynamic conditions favorable for TC formation. In 2021. the IOBM quickly turned to a warm anomaly in March and persisted until summer, whereas the PMM became a negative phase in January and remained so until summer. At the same time,the MJO stagnated in phases 2 and 3 for up to 47 days, with the center of convection located over the western Maritime Continent, producing conditions unconducive to TC ge

关键词： Tropical cyclone La Nina events Indian Ocean Basin Mode Pacific Meridional Mode Madden-Julian Oscillation Western Pacific Subtropical High Monsoon trough

Exploring a Promising Region and Enhancing Decision Space Diversity for Multimodal Multi-Objective Optimization

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Tsinghua Science and Technology 2024年第2期29卷 325-342页

作者： Fei Ming Wenyin gong School of Computer Science China University of GeosciencesWuhan 430074China

During the past decade,research efforts have been gradually directed to the widely existing yet less noticed multimodal multi-objective optimization problems(MMOPs)in the multi-objective optimization ***,researchers have begun to investigate enhancing the decision space diversity and preserving valuable dominated solutions to overcome the shortage caused by a preference for objective space ***,many existing methods still have limitations,such as giving unduly high priorities to convergence and insufficient ability to enhance decision space *** overcome these shortcomings,this article aims to explore a promising region(PR)and enhance the decision space diversity for handling *** traditional methods,we propose the use of non-dominated solutions to determine a limited region in the PR in the decision space,where the Pareto sets(PSs)are included,and explore this region to assist in solving ***,we develop a novel neighbor distance measure that is more suitable for the complex geometry of PSs in the decision space than the crowding *** on the above methods,we propose a novel dual-population-based coevolutionary *** studies on three benchmark test suites demonstrates that our proposed methods can achieve promising performance and versatility on different *** effectiveness of the proposed neighbor distance has also been justified through comparisons with crowding distance methods.

关键词： multimodal multi-objective optimization evolutionary algorithms promising region neighbor distance decision space coevolution