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Frontiers in Energy 2019年第3期13卷 483-493页

作者： xiang LI Wenzheng ZHANG Zhong HUANG Dehao JU Li HUANG Mingzhi feng Xingcai LU Zhen HUANG Key Laboratory of Power Machinery and Engineering Ministry of EducationShanghai Jiao Tong UniversityShanghai 200240China Shanghai Marine Diesel Engine Research Institute Shanghai 201108China

Liquefied natural gas (LNG), mainly composed of methane, is in progress to substitute diesel fuel in heavyduty marine engine for practical, economic, and environmental considerations. However, natural gas is relatively difficult to be ignited in a large bore combustion chamber. A combustion enhancement technique called prechamber turbulent jet ignition (TJI) can permit combustion and flame propagation in a largebore volume. To investigate the effect of air-fuel equivalence ratio and pre-mixed pressure on pre-chamber TJI of methane/air mixtures with multiple orifices in a large bore volume, experimental tests and computational simulations were implemented to study the discharge of hot turbulent jets from six orifices of the pre-chamber. Different initial pressures and air-fuel equivalence ratios were considered to analyze the characteristics of TJI. The asymmetry of the turbulent jet actuated from six different orifices were found due to the asymmetric orientation of the spark plug, resulting in the inhomogeneous distribution of combustion in the constant volume chamber, which should be considered seriously in the marine engine design. Besides,as the premixed pressure increases, it has more effect on the flame propagation and plays a more important role, as it further increases.

关键词： marine engine natural gas methane turbulent jet ignition (TJI) pre-chamber

Automatic Detection of Weld Defects in Pressure Vessel X-Ray Image Based on CNN

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Wuhan University Journal of Natural Sciences 2022年第6期27卷 489-498页

作者： XIAO Wenkai Feng xiang NAN Shuiyu ZHANG Linlin Department of Computer Science and Engineering.East China University of Science and Technology Shanghai 200237China Shanghai Engineering Research Center of Smart Energy Shanghai 201103China Shanghai Aino Industrial Technology CO..LTD.Shanghai 201612 China

The visual automatic detection method based on artificial intelligence has attracted more and more attention. In order to improve the performance of weld nondestructive defect detection,we propose DRepDet(Dilated RepPoints Detector). First, we analyze the weld defect dataset in detail and summarize the distribution characteristics of weld defect data, that is, the defect scale is very different and the aspect ratio distribution range is large. Second, according to the distribution characteristics of defect data, we design DResBlock module, and introduce dilated convolution with different dilated rates in the process of feature extraction to expand the receptive field and improve the detection performance of large-scale defects. Based on DResBlock and anchor-free detection framework RepPoints, we design DRepDet. Extensive experiments show that our proposed detector can detect 7 types of defects. When using combined dilated rate convolution network in detection, the AP50 and Recall50 of big defects are improved by 3.1% and 3.3% respectively, while the performance of small defects is not affected, almost the same or slightly improved. The final performance of the whole network is improved a large margin,with 6% AP50 and 4.2% Recall50 compared with Cascade RCNN and 1.4% AP50 and 2.9% Recall50 compared with RepPoints.

关键词： nondestructive testing depth learning weld defect detection convolutional neural networks dilated convolution

Fate of undigested proteins in the pig large intestine:What impact on the colon epithelium?

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Animal Nutrition 2022年第2期9卷 110-118页

作者： François Blachier Mireille Andriamihaja xiang-feng Kong UMR PNCA Nutrition Physiology and Alimentary BehaviorUniversite Paris-SaclayAgroParisTechINRAEParisFrance Key Laboratory of Agro-Ecological Processes in Subtropical Region Institute of Subtropical AgricultureChinese Academy of SciencesChangshaChina

Apart from its obvious agronomic interest in feeding billions of people worldwide,the porcine species represents an irreplaceable experimental model for intestinal physiologists and nutritionists.In this review,we give an overview on the fate of proteins that are not fully digested in the pig small intestine,and thus are transferred into the large intestine.In the large intestine,dietary and endogenous proteins are converted to peptides and amino acids(AA)by the action of bacterial proteases and peptidases.AA,which cannot,except in the neonatal period,be absorbed to any significant level by the colonocytes,are used by the intestinal microbes for protein synthesis and for the production of numerous metabolites.Of note,the production of the AA-derived metabolites greatly depends on the amount of undigested polysaccharides in the pig's diet.The effects of these AA-derived bacterial metabolites on the pig colonic epithelium have not yet been largely studied.However,the available data,performed on colonic mucosa,isolated colonic crypts and colonocytes,indicate that some of them,like ammonia,butyrate,acetate,hydrogen sulfide(H_(2)S),and p-cresol are active either directly or indirectly on energy metabolism in colonic epithelial cells.Further studies in that area will certainly gain from the utilization of the pig colonic organoid model,which allows for disposal of functional epithelial unities.Such studies will contribute to a better understanding of the potential causal links between diet-induced changes in the luminal concentrations of these AA-derived bacterial metabolites and effects on the colon epithelial barrier function and water/electrolyte absorption.

关键词： Gut microbiota Amino acids Bacterial metabolites Pig Large intestine

Key nanomaterials for industrial chemical process

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Nano Research 2023年第5期16卷 6013-6014页

作者： xiang feng Han Hu De Chen State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao 266580China Department of Chemical Engineering Norwegian University of Science and TechnologyTrondheim 7491Norway

Growing concerns about the increasing global energy consumption and CO_(2)emission have greatly accelerated the development of new nanotechnologies in industrial chemical processes.However,this poses huge scientific and technological challenges,and normally requires novel materials and also novel synthesis strategies for traditional nanomaterials.This topical collection includes some of the latest studies on nanoscience and nanotechnology in chemical processes,such as separation,energy storage,and catalytic reactions(e.g.,hydrogenation,dehydrogenation,hydrogen evolution,selective oxidation,C–C coupling,and C–O bond formation).It includes 4 topics:(i)nanoscience and nanotechnology towards industrial process;(ii)nanomaterials for novel green chemical processes;(iii)novel nanomaterials for traditional processes;and(iv)novel synthesis strategy for nanomaterials.

关键词： materials chemical process

“一带一路”建设中知识产权保护的挑战与对策

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理论视野 2018年第8期 85-88页

作者：王志刚 Feng xiang 山西省运城市委党校理论政策研究室

"一带一路"建设中,相关国家贸易往来日趋频繁,跨国交易、技术贸易、对外投资等活动中,必然涉及到知识产权的市场交易、专利保护、法庭诉讼等一系列问题。各国应准确把握知识产权保护所面临的挑战,并采取行之有效的措施加以解决。

关键词：一带一路知识产权保护挑战对策

Nonlinear amplitude inversion using a hybrid quantum genetic algorithm and the exact zoeppritz equation

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Petroleum Science 2022年第3期19卷 1048-1064页

作者： Ji-Wei Cheng feng Zhang xiang-Yang Li College of Geophysics State Key Laboratory of Petroleum Resources and ProspectingChina University of Petroleum(Beijing)Beijing102249China British Geological Survey EdinburghUK

The amplitude versus offset/angle(AVO/AVA)inversion which recovers elastic properties of subsurface media is an essential tool in oil and gas exploration.In general,the exact Zoeppritz equation has a relatively high accuracy in modelling the reflection coefficients.However,amplitude inversion based on it is highly nonlinear,thus,requires nonlinear inversion techniques like the genetic algorithm(GA)which has been widely applied in seismology.The quantum genetic algorithm(QGA)is a variant of the GA that enjoys the advantages of quantum computing,such as qubits and superposition of states.It,however,suffers from limitations in the areas of convergence rate and escaping local minima.To address these shortcomings,in this study,we propose a hybrid quantum genetic algorithm(HQGA)that combines a self-adaptive rotating strategy,and operations of quantum mutation and catastrophe.While the selfadaptive rotating strategy improves the flexibility and efficiency of a quantum rotating gate,the operations of quantum mutation and catastrophe enhance the local and global search abilities,respectively.Using the exact Zoeppritz equation,the HQGA was applied to both synthetic and field seismic data inversion and the results were compared to those of the GA and QGA.A number of the synthetic tests show that the HQGA requires fewer searches to converge to the global solution and the inversion results have generally higher accuracy.The application to field data reveals a good agreement between the inverted parameters and real logs.

关键词： Nonlinear inversion AVO/AVA inversion Hybrid quantum genetic algorithm(HQGA)

Ultra-low-power backscatter-based software-defined radio for intelligent and simplified IoT network

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Frontiers of Information Technology & Electronic Engineering 2022年第1期23卷 19-30页

作者： Huixin DONG Wei KUANG Fei XIAO Lihai LIU Feng xiang Wei WANG Jianhua HE School of Electronic Information and Communication Huazhong University of Science and TechnologyWuhan430074China School of Management Huazhong University of Science and TechnologyWuhan430074China China Railway Siyuan Survey and Design Group Co. Ltd.Wuhan430063China Wuhan Maritime Communication Research Institute Wuhan430079China School of Computer Science and Electronic Engineering University of EssexColchesterCO43SQUK

The recent decade has witnessed an upsurge in the demands of intelligent and simplified Internet of Things(IoT)networks that provide ultra-low-power communication for numerous miniaturized devices.Although the research community has paid great attention to wireless protocol designs for these networks,researchers are handicapped by the lack of an energy-efficient software-defined radio(SDR)platform for fast implementation and experimental evaluation.Current SDRs perform well in battery-equipped systems,but fail to support miniaturized IoT devices with stringent hardware and power constraints.This paper takes the first step toward designing an ultra-low-power SDR that satisfies the ultra-low-power or even battery-free requirements of intelligent and simplified IoT networks.To achieve this goal,the core technique is the effective integration ofµW-level backscatter in our SDR to sidestep power-hungry active radio frequency chains.We carefully develop a novel circuit design for efficient energy harvesting and power control,and devise a competent solution for eliminating the harmonic and mirror frequencies caused by backscatter hardware.We evaluate the proposed SDR using different modulation schemes,and it achieves a high data rate of 100 kb/s with power consumption less than 200µW in the active mode and as low as 10µW in the sleep mode.We also conduct a case study of railway inspection using our platform,achieving 1 kb/s battery-free data delivery to the monitoring unmanned aerial vehicle at a distance of 50 m in a real-world environment,and provide two case studies on smart factories and logistic distribution to explore the application of our platform.

关键词： Backscatter Ultra-low-power SDR IoT networks

The use of phalangeal plate as“hook plate”and external fixation to treat complex distal radius fracture fragments

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World Journal of Emergency Medicine 2022年第4期13卷 322-325页

作者： xiang-feng Zhang Edem Prince Ghamor-Amegavi He-jia Hu Gang feng Department of Orthopedic Surgery the Second Affiliated Hospital of Zhejiang University School of MedicineHangzhou 310009China

Distal radius fracture is the most common fracture site of the human skeleton[1]and often occurs in young people resulting from high energy injury caused by severe trauma.However,complex distal radial intra-articular fractures(AO type C3)are relatively rare and account for about 5%of all distal radius fractures.[2]Fracture comminution at the joint surface is the primary manifestation of these fractures,followed by avulsion of the bone fragments with displacement seen at both the metacarpal and ulnar bone.Treatment of these displaced and unstable fractures remains a challenge.The nature of the articular surface fracture indicates the use of either the open or close reduction technique.Treatment protocols focus on extra-articular reduction and restoration of radial length,maintaining the volar tilt.[3,4]It has been noted that incongruity of the intra-articular distal radius fracture is relevant to the development of arthritis.[5,6]

关键词： unstable radius fracture

Economic benefits of Northeast Asia energy interconnection:A quantitative analysis based on a computable general equilibrium model

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Global Energy Interconnection 2021年第3期4卷 295-303页

作者： Jian Wang Shenghao feng Junyong xiang Global Energy Interconnection Development and Cooperation Organization No.8 Xuanwumennei StreetBeijing 100031P.R.China Research Institute for Global Value Chains University of International Business and EconomicsHuixindong StreetBeijing100029P.R.China

There has been an intense discussion on the energy infrastructure cooperation in Northeast Asia.Most studies have focused on the technical feasibility of grid interconnection,deployment of renewable energy,and have ignored the quantitative analysis of social and economic benefits of these proposals.This study uses a computable general equilibrium model to evaluate the effects of energy interconnection in Northeast Asia.Key model development tasks include 1)constructing a new nesting structure,2)econometrically estimating the constant elasticities of substitution(CES)between fossil-and non-fossil-power generation bundles,3)developing a new base-case scenario,and 4)developing the policy scenario.We found that while Northeast Asia will benefit from energy interconnection development with higher GDP than in the base-case;there will be a trade-off between higher investment and lower consumption.Sector results and environmental implications in this region are also discussed.

关键词： Global Energy Interconnection CGE Economic impacts Northeast Asia

Crystalline,Rheological and Mechanical Enhancement in PBAT/PPC/Silica Nanocomposites with Double Percolation Network

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Chinese Journal of Polymer Science 2022年第11期40卷 1482-1492页

作者： You-Mei Ma feng-xiang Gao Shu-Ling Zhang College of Chemistry Jilin UniversityChangchun130012China Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China

Nanocomposites of blends of biodegradable poly(butylene adipate-co-terephthalate)(PBAT)and sustainable poly(propylene carbonate)(PPC)with nanosilica were prepared by melt compounding method.PBAT/PPC blend was partially miscible system with sea-island structure,and nanosilica particles were selectively dispersed in the continuous phase PBAT matrix to form the double percolation network.The introduction of nanosilica into PBAT/PPC blend reduced the size of dispersed PPC phase,promoted the crystallization of PBAT in the nanocomposites,and increased the storage modulus of the nanocomposites.The study of rheological behaviors indicated that the double percolation network was formed at the nanosilica loading of 5 wt%,as a result,the nanocomposites exhibited the solid-like viscoelastic behavior and their relaxation time was extended.With the increase of the nanosilica content,the PBAT/PPC/silica nanocomposites displayed increased Young's modulus and yield strength.

关键词： Nanocomposites Selective dispersion Double percolation Enhanced properties