检索结果-南通市图书馆

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

李祥云补肾祛瘀法改善子宫内膜容受性经验

中国中医基础医学杂志 2018年第9期24卷 1322-1324页

作者：李雪莲李祥云复旦大学附属妇产科医院妇科上海200011 上海市女性生殖内分泌相关疾病重点实验室上海200011 上海中医药大学附属龙华医院妇科上海200032

子宫内膜容受性指母体子宫内膜对胚胎的接受能力,是决定胚胎顺利着床的关键因素。全国名老中医李祥云教授认为"肾虚瘀阻"是子宫内膜容受性下降之根本,肾气不足则气血运行不畅、瘀滞内生,日久则脏腑功能失司又加重肾虚;治疗以"补肾祛瘀"... 详细信息

子宫内膜容受性指母体子宫内膜对胚胎的接受能力,是决定胚胎顺利着床的关键因素。全国名老中医李祥云教授认为"肾虚瘀阻"是子宫内膜容受性下降之根本,肾气不足则气血运行不畅、瘀滞内生,日久则脏腑功能失司又加重肾虚;治疗以"补肾祛瘀"为基本原则,用活血祛瘀药改善微循环、降低血液黏稠度、改善血供,提高子宫内膜容受性,同时根据"肾虚"和"瘀阻"的侧重并兼顾月经周期微调用药,进一步提高妊娠率,改善妊娠结局。

关键词：子宫内膜容受性肾虚瘀阻补肾祛瘀

Reliability analysis for wireless communication networks via dynamic Bayesian network

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2023年第5期34卷 1368-1374页

作者： YANG Shunqi ZENG Ying LI Xiang li Yanfeng HUANG Hongzhong School of Naval Architecture and Ocean Engineering Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 611731China China University of Petroleum at Karamay Karamay 834000China

The dynamic wireless communication network is a complex network that needs to consider various influence factors including communication devices,radio propagation,network topology,and dynamic behaviors.Existing works focus on suggesting simplified reliability analysis methods for these dynamic networks.As one of the most popular modeling methodologies,the dynamic Bayesian network(DBN)is proposed.However,it is insufficient for the wireless communication network which contains temporal and non-temporal events.To this end,we present a modeling methodology for a generalized continuous time Bayesian network(CTBN)with a 2-state conditional probability table(CPT).Moreover,a comprehensive reliability analysis method for communication devices and radio propagation is suggested.The proposed methodology is verified by a reliability analysis of a real wireless communication network.

关键词： dynamic Bayesian network(DBN) wireless commu-nication network continuous time Bayesian network(CTBN) network reliability

The Pathway of China’s Integrated Delivery System:Based on the Analysis of the Medical Consortium Policies

在线全文

学校读者我要写书评

暂无评论

Current Medical Science 2022年第6期42卷 1164-1171页

作者： Huan GAO Xing-li DU Jia-zhi liAO LI Xiang School of Medicine and Health Management Huazhong University of Science and TechnologyWuhan430030China Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

With the deepening of China’s health-care reform,an integrated delivery system has gradually emerged with the function of improving the efficiency of the health-care delivery system.For China’s integrated delivery system,a medical consortium plays an important role in integrating public hospitals and primary care facilities.The first medical consortium policy issued after the COVID-19 pandemic apparently placed hope on accelerating the implementation of a medical consortium and tiered health-care delivery system.This paper illustrates the possible future pathway of China’s medical consortium through retrospection of the 10-year process,changes of the series of policies,and characteristics of the policy issued in 2020.We considered that a fully integrated medical consortium would be a major phenomenon in China's medical industry,which would lead to the formation of a dualistic care pattern in China.

关键词： health-care reform integrated delivery system medical consortium tiered health-care delivery system health policy

Atomic regulations of single atom from metal-organic framework derived carbon for advanced water treatment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2023年第7期16卷 10326-10341页

作者： xiang li Bo Wang Key Laboratory of Cluster Science Ministry of Education Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion MaterialsAdvanced Technologies Research Institute(Jinan)Advanced Research Institute of Multidisciplinary ScienceSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyNo.5South StreetZhongguancunHaidian DistrictBeijing 100081China

Single atom(SA)-embedded nitrogen-doped carbon has shown great potential in environmental remediation.Nowadays,engineered nanomaterials(ENMs)have attracted great research interests in recent years.Metal-organic framework(MOF)derived SAs show the advantages of tunable topology and averaged separated active sites.SAs bridge the gap between homogeneous and heterogeneous catalysts.The reaction efficiency can be significantly improved by designing the MOFs derived from carbon and SAs.In this review,the research advanced in MOFs-derived carbon and SAs in advanced oxidation process(AOP)in water were summarized.Major strategies to fabricate the SAs derived from MOFs were discussed,including the mixed/single metal strategy,metal-containing linker strategy,pore confinement strategy,thermal diffusion strategy,and pyrolysis MOFs with bulk metals.Advanced characterization technologies have been introduced,including electron microscopy and spectroscopic methods.To explain the catalytic mechanism for various applications,the relationship between the performance and the atomic configuration was systematically discussed.Recent applications of the MOFs derived from carbon and SAs have been summarized.A series of the latest work on effectively removing pollutants by SAs are also listed.Based on the fundamental knowledge and recent practical application of MOFs-derived carbon and SAs,some perspectives on the further directions were presented.This review offers guidance for applying novel engineered nanomaterials in the water treatment field.

关键词： single-atom catalysts(SACs) engineered nanomaterials(ENMs) metal-organic framework(MOF) MOFs derived carbon water treatment

A Voronoi diagram approach for detecting defects in 3D printed fiber-reinforced polymers from microscope images

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computational Visual Media 2023年第1期9卷 41-56页

作者： xiang li Sara McMains University of California Berkeley BerkeleyCalifornia94720USA

Fiber-reinforced polymer(FRP)composites are increasingly popular due to their superior strength to weight ratio.In contrast to significant recent advances in automating the FRP manufacturing process via 3D printing,quality inspection and defect detection remain largely manual and inefficient.In this paper,we propose a new approach to automatically detect,from microscope images,one of the major defects in 3D printed FRP parts:fiber-deficient areas(or equivalently,resin-rich areas).From cross-sectional microscope images,we detect the locations and sizes of fibers,construct their Voronoi diagram,and employ-shape theory to determine fiber-deficient areas.Our Voronoi diagram and-shape construction algorithms are specialized to exploit typical characteristics of 3D printed FRP parts,giving significant efficiency gains.Our algorithms robustly handle real-world inputs containing hundreds of thousands of fiber cross-sections,whether in general or non-general position.

关键词： 3D printing(3DP) microscope image processing fiber-reinforced polymer(FRP) Voronoi diagrams -shapes resin-rich areas

An assessment of the CMIP5 models in simulating the Argo geostrophic meridional transport in the North Pacifi c Ocean

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Oceanology and limnology 2020年第5期38卷 1445-1463页

作者： LI Xiang YUAN Dongliang Key Laboratory of Ocean Circulation and Waves Institute of OceanologyChinese Academy of Sciencesand Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266071China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Eleven climate system models that participate in the Coupled Model Intercomparison Project phase 5(CMIP5)were evaluated based on an assessment of their simulated meridional transports in comparison with the Sverdrup transports.The analyses show that the simulated North Pacifi c Ocean circulation is essentially in Sverdrup balance in most of the 11 models while the Argo geostrophic meridional transports indicate signifi cant non-Sverdrup gyre circulation in the tropical North Pacifi c Ocean.The climate models overestimated the observed tropical and subtropical volume transports signifi cantly.The non-Sverdrup gyre circulation leads to non-Sverdrup heat and salt transports,the absence of which in the CMIP5 simulations suggests defi ciencies of the CMIP5 model dynamics in simulating the realistic meridional volume,heat,and salt transports of the ocean.

关键词： Coupled Model Intercomparison Project phase 5(CMIP5)models Sverdrup balance meridional transport Argo geostrophic currents

APF-GAN:Exploring asymmetric pre-training and fine-tuning strategy for conditional generative adversarial network

在线全文

学校读者我要写书评

暂无评论

Computational Visual Media 2024年第1期10卷 187-192页

作者： Yuxuan li lingfeng Yang xiang li College of Computer Science Nankai UniversityTianjinChina School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjingChina

The use of generative adversarial network(GAN)-based models for the conditional generation of image semantic segmentation has shown promising results in recent years.However,there are still some limitations,including limited diversity of image style,distortion of detailed texture,unbalanced color tone,and lengthy training time.To address these issues,we propose an asymmetric pre-training and fine-tuning(APF)-GAN model.

关键词： tuning network asymmetric

Review on Metal-Acid Tandem Catalysis for Hydrogenative Rearrangement of Furfurals to C_(5) Cyclic Compounds

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Tianjin University 2023年第5期29卷 347-359页

作者： xiang li Qiang Deng School of Chemistry and Chemical Engineering Nanchang UniversityNo.999 Xuefu AvenueNanchang 330031China College of Forestry Jiangxi Agricultural UniversityNo.1101 Zhimin AvenueNanchang 330045China

Hydrogenative rearrangement of biomas s-derived furfurals(furfural and 5-hydroxymethyl furfural) to C_(5) cyclic compounds(such as cyclopentanones and cyclopentanols) offers an expedient reaction route for acquiring O-containing value-added chemicals thereby replacing the traditional petroleum-based approaches.The scope for developing efficient bifunctional catalysts and establishing mild reaction conditions for upgrading furfurals to cyclic compounds has stimulated immense deliberation in recent years.Extensive efforts have been made toward developing catalysts for multiple tandem conversions,including those with various metals and supports.In this scientific review,we aim to summarize the research progress on the synergistic effect of the metal-acid sites,including simple metal-supported acidic supports,adjacent metal acid sites-supported catalysts,and in situ H_(2)-modified bifunctional catalysts.Distinctively,the catalytic performance,catalytic mechanism,and future challenges for the hydrogenative rearrangement are elaborated in detail.The methods highlighted in this review promote the development of C_(5) cyclic compound synthesis and provide insights to regulate bifunctional catalysis for other applications.

关键词： Bifunctional catalysts Furfurals Hydrogenative rearrangement C_(5)cyclic compounds Synergistic catalysis

Toward the minimum vertex cover of complex networks using distributed potential games

在线全文

学校读者我要写书评

暂无评论

Science China(Information Sciences) 2023年第1期66卷 244-263页

作者： Jie CHEN xiang li Adaptive Networks and Control Lab Department of Electronic Engineering Fudan University Institute of Complex Networks and Intelligent Systems Shanghai Research Institute for Intelligent Autonomous SystemsTongji University

Vertex cover of complex networks is essentially a major combinatorial optimization problem in network science, which has wide application potentials in engineering. To optimally cover the vertices of complex networks, this paper employs a potential game for the vertex cover problem, designs a novel cost function for network vertices, and proves that the solutions to the minimum value of the potential function are the minimum vertex covering(MVC) states of a general complex network. To achieve the optimal(minimum) covering states, we propose a novel distributed time-variant binary log-linear learning algorithm,and prove that the MVC state of a general complex network is attained under the proposed optimization algorithm. Furthermore, we estimate the upper bound of the convergence rate of the proposed algorithm,and show its effectiveness and superiority using numerical examples with representative complex networks and optimization algorithms.

关键词： minimum vertex cover Nash equilibrium convergence rate scale-free network random graph