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Deformation characterization method of typical double-walled turbine blade structure during casting process

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Journal of Iron and Steel Research(International) 2023年第10期30卷 2010-2020页

作者： Yi-wei Dong Peng-Fei Shao Xiang Guo Bo Xu Chun-ping Yin Zhi-yong Tan School of Aerospace Engineering Xiamen UniversityXiamen 361005FujianChina AECC Commercial Aircraft Engine Co. Ltd.Shanghai 200241China

To address the complex structures,large out-of-tolerance issues,and inconsistent quality of double-walled turbine blades,a mapping relationship between the structure and deformation was established based on a structural correlation study.Numerical simulations and pouring experiments were carried out based on the designed double-walled model,and a reliable displacement field model of the double-walled blade was established.A decoupling method for the displacement field of the double-walled blade castings was proposed,which decoupled the displacement field into bending,torsion,and expansion/shrinkage deformation vectors.Based on the displacement field analysis of the theoretical and physical models,an expansion/shrinkage model of double-walled blade structure castings was established.Furthermore,an experiment to determine the mapping relationship between double-walled construction and deformation was designed,which included the characteristic distribution distance and designed angle as structural parameters.The functional relationship between the deformation and the structural parameters was established based on a nonlinear regression method.

关键词： Turbine blade Double-walled structure Deformation decoupling Expansion/shrinkage model Structure-deformation mapping

Synthesis of structurally diversified BINOLs and NOBINs via palladium-catalyzed C-H arylation with diazoquinones

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Science China Chemistry 2021年第9期64卷 1515-1521页

作者： Ji-Wei Zhang fei Jiang Ye-Hui Chen shao-Hua Xiang Bin Tan School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin150001China Shenzhen Grubbs Institute and Department of Chemistry Southern University of Science and TechnologyShenzhen518055China Academy for Advanced Interdisciplinary Studies Southern University of Science and TechnologyShenzhen518055China

Privileged biaryl frameworks,BINOL and NOBIN,were efficiently constructed with sole 1-DNQs as arylation reagents under one set of reaction conditions.The judicious selection of palladium-catalytic system plays a pivotal role in the excellent selectivities.This transformation accommodated fairly broad substrate generality for both 2-naphthol and N-Boc-2-naphthylamine and afforded the structurally diversified BINOLs and NOBIN derivatives in high efficiency.Notably,the bromosubstituents which cannot survive in conventional palladium-catalyzed reactions were well-compatible with this set of conditions,providing an effective handle for further enriching the library of BINOLs and NOBINs.Preliminary attempts on the asymmetric variant of this reaction were also performed with up to 80:20 er for BINOLs synthesis.

关键词： BINOLs NOBINs high selectivity C-H arylation palladium-catalysis

Methodological Issues and Values Arising from the Construction of a Heritage Corridor Along Chinese Eastern Railway

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China City Planning Review 2016年第2期25卷 8-17页

作者： Gao fei shao Long Harbin Institute of Technology

The Chinese Eastern Railway(CER),which was designed by Russia in 1898 and constructed later by China,is a typical industrial cultural landscape of the 20 th century that enjoys a high uniqueness and representativeness due to its integrality and systematicness.It sits on a historic site with various kinds of resources,including architecture,railways,and other facilities.As there has been few changes with CER's route,its resources are,in fact,still serviceable to the current railway system and people living along the route.However,considering the problems,such as lack of maintenance,ignorance of the society,inappropriate renovations,etc.,attention should be paid to CER's value assessment before any reconstruction decisions are made.Although value assessment plays a very important role in the decision-making and investment-planning process,there is almost no related research on the construction of a heritage corridor along CER.Seeing that value assessment is part of the CER Heritage Corridor construction project and the values act as a reference in understanding CER as a heritage site,this paper aims to put forward a methodological guidance to identify CER's values,so that its resources will be assessed by using what we call "value typology." In addition,it also tries to promote the tools that can help to evaluate CER's values.On the basis of a methodological analysis,it finally puts forward some advices to integrating the value assessment into the decision-making process.

关键词： value assessment heritage corridor construction Chinese Eastern Railway methodological issues

Adaptive-measurement based quantum tomography

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Science China(Physics,Mechanics & Astronomy) 2017年第2期60卷 76-77页

作者： shao-Ming fei School of Mathematical Sciences Capital Normal University Beijing 100048 China

Quantum state tomography(QST)concerns a complete description of arbitrary unknown quantum states by using experimental data from quantum measurements.The adaptive measurement,i.e.,repeated measurement of an observable utilizing prior measurement outcomes and adapting to changing experimental conditions,has great potential for various purposes in quantum information sciences like QST.An open problem left for QST is how many measurements are needed to determine unknown quantum states.

关键词：自适应测量层析成像量子态量子信息科学 QST 量子状态实验数据量子测量

Iridium-Catalyzed Asymmetric Hydrogenation of Tetrasubstituted Exocyclic Olefins:An Efficient Access to Dexmethylphenidate

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CCS Chemistry 2023年第12期5卷 2808-2817页

作者： Yingying Tian Yu-Yi Zhu Jianchao Yu Dong-Huang Liu Qin Yin shao-fei Ni shao-Tao Bai Xumu Zhang Department of Chemistry Shenzhen Grubbs InstituteSouthern University of Science and TechnologyShenzhen Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province Shantou UniversityShantou Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen Institute of Carbon-Neutral Technology and Center for Carbon-Neutrality Catalysis and Engineering Shenzhen Polytechnic UniversityShenzhen

An Ir-catalyzed enantioselective hydrogenation of challenging tetrasubstituted exocyclic olefins is disclosed.This new catalytic system tolerates a broad substrate scope and affords valuable chiral cyclic β-amino esters possessing two vicinal stereocenters in high yields and excellent enantioselectivities and diastereoselectivities(up to 94% yield,96% ee,99:1 dr).Control experiments and deuterium-labeling reactions reveal an iminium hydrogenation mechanism upon Brønsted acid-promoted tautomerization of the C=C double bond to cycliciminium intermediates.Density functional theory calculations showcase that the excellent selectivities are derived from C-H…π interaction between the substrate and the chiral ligand.Application in gram-scale preparation of dexmethylphenidate with up to 1500 turnover number is also demonstrated,showing the promising potential of Ir-catalyzed enantioselective hydrogenation in drug synthesis.

关键词： asymmetric hydrogenation tetrasubstituted olefins iridium Bronsted acids dexmethylphenidate

Progressive framework for deep neural networks: from linear to non-linear

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The Journal of China Universities of Posts and Telecommunications 2016年第6期23卷 1-7页

作者： shao Jie Zhao Zhicheng Su fei Cai Anni School of Information and Communication Engineering Beijing University of Posts and Telecommunications Beijing Key Laboratory of Network System and Network Culture Beijing University of Posts and Telecommunications

We propose a novel progressive framework to optimize deep neural networks. The idea is to try to combine the stability of linear methods and the ability of learning complex and abstract internal representations of deep leaming methods. We insert a linear loss layer between the input layer and the first hidden non-linear layer of a traditional deep model. The loss objective for optimization is a weighted sum of linear loss of the added new layer and non-linear loss of the last output layer. We modify the model structure of deep canonical correlation analysis （DCCA）, i.e., adding a third semantic view to regularize text and image pairs and embedding the structure into our framework, for cross-modal retrieval tasks such as text-to-image search and image-to-text search. The experimental results show the performance of the modified model is better than similar state-of-art approaches on a dataset of National University of Singapore （NUS-WIDE）. To validate the generalization ability of our framework, we apply our framework to RankNet, a ranking model optimized by stochastic gradient descent. Our method outperforms RankNet and converges more quickly, which indicates our progressive framework could provide a better and faster solution for deep neural networks.

关键词： framework neural network DCCA semantic RankNet

Jet Noise Reduction of Double-Mixing Exhaust System

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Transactions of Nanjing University of Aeronautics and Astronautics 2016年第2期33卷 129-136页

作者： shao Wanren Wu fei He Jingyu Li Xiaodong Shenyang Engine Design and Research Institute Aviation Industry Corporation of China Shenyang 110015 P.R. China China Academy of Aerospace Aerodynamics Beijing 100074 P.R. China School of Energy and Power Engineering Beihang University Beijing 100191 P.R. China

A jet noise reduction technique by using the external chevron nozzle with lobed mixer in the double-mixing exhaust system is investigated under cold conditions.The computations of jet field and the experiments of noise field are conducted with scaled model of high-bypass-ratio turbofan engine mixing exhaust system composed of external chevron nozzle with lobed mixer.The computational results indicate that comparing with the baseline nozzle with lobed mixer,the external chevron nozzle with lobed mixer increases mixing of jet and ambient air near the nozzle exit.The experimental results show that the external chevron nozzle with lobed mixer has better jet noise reduction at low frequencies,and this reduction rises with the increase of chevron bend angle.The experimental results also show that the external chevron nozzle with lobed mixer has sound pressure level(SPL)increase which is not obvious at high frequencies.With chevron bend angle increasing,SPL has relatively marked increase at 60°(directivity angle measured from upstream jet axis)and little fluctuations at 90°and 150°.The external chevron nozzle with lobed mixer has overall sound pressure level(OASPL)reduction in varying degrees at 60°and 150°,but it has little OASPL increase at 90°.

关键词： aerospace propulsion system high-bypass-ratio turbofan engine mixing exhaust system lobed mixer chevron nozzle jet noise reduction

Entanglement concentration of W-class states on nonlocal atoms using low-Q optical cavity

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Science China Earth Sciences 2016年第12期59卷 235-236页

作者： shao-Ming fei School of Mathematical Sciences Capital Normal University

As one of the most striking features of quantum phenomena,quantum entanglement has been identified as a key nonlocal resource in quantum information processing such as quantum cryptography[1–3].In particular,the maximally entangled states give rise to the best fidelity in general,for instance,perfect teleportation.Nevertheless,in practical,during the transmission of quantum entanglement,a maximally entangled

关键词：量子纠缠光学谐振腔低品质浓缩原子局域量子信息处理量子隐形传态

工业机器人、技能结构升级与企业劳动收入份额

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吉林大学社会科学学报 2024年第3期64卷 144-165,238页

作者：余长林邵飞飞厦门大学宏观经济研究中心暨邹至庄经济研究院厦门大学经济学院厦门361005

提高劳动报酬在初次分配中的比重是促进共同富裕的基础。机器人应用在引发企业生产力与生产方式变革的同时,将如何重塑生产要素分配格局?为此,文章通过构建理论模型探讨了工业机器人对企业劳动收入份额的影响机理,并利用中国制造业A股... 详细信息

提高劳动报酬在初次分配中的比重是促进共同富裕的基础。机器人应用在引发企业生产力与生产方式变革的同时,将如何重塑生产要素分配格局?为此,文章通过构建理论模型探讨了工业机器人对企业劳动收入份额的影响机理,并利用中国制造业A股上市公司数据实证考察了工业机器人应用对制造企业劳动收入份额的影响。研究发现,工业机器人应用提高了制造企业劳动收入份额,内生性检验和稳健性检验进一步支持了该结论。基于学历和岗位双重维度的机制分析表明,工业机器人应用主要通过技能结构升级提高企业劳动收入份额。异质性分析表明,在国有企业、技术人员占比低的企业、资本密集型行业、资本劳动替代弹性小的行业、中西部地区和有政策支持的地区,工业机器人应用对企业劳动收入份额的提升作用更为显著。

关键词：工业机器人劳动收入份额技能结构升级技能偏向性