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Chinese Journal of Aeronautics 2014年第4期27卷 846-855页

作者： chen hongxia chen Yunxia Yang Zhou School of Reliability and Systems Engineering Beihang University

Fatigue induced products generally bear fatigue loads accompanied by impact processes,which reduces their reliable life rapidly. This paper introduces a reliability assessment model based on a local stress–strain approach considering both low-cycle fatigue and high energy impact *** coupling relationships between fatigue and impact are given with effects of an impact process on fatigue damage and effects of fatigue damage on impact performance. The analysis of the former modifies the fatigue parameters and the Manson–Coffin equation for fatigue life based on material theories. On the other hand, the latter proposes the coupling variables and the difference of fracture toughness caused by accumulative fatigue damage. To form an overall reliability model including both fatigue failure and impact failure, a competing risk model is developed. A case study of an actuator cylinder is given to validate this method.

关键词： Coupling damage Fatigue High-energy impactLow-cycle Local stress-strain Reliability Strain rate

Empirical Study on Effect of Industrial Structure Change on Regional Economic Growth of Beijing-Tianjin-Hebei Metropolitan Region

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Chinese Geographical Science 2011年第6期21卷 708-714页

作者： chen hongxia LI Guoping School of Government Central University of Finance and Economics Beifing 100081 China School of Government Peking University Beijing 100871 China

Based on the data of gross domestic product(GDP),industrial added value and the proportion of industrial employees from 2000 to 2008,this paper studies the effect of industrial structure change on the regional economic growth of Beijing-Tianjin-Hebei Metropolitan Region in China using the shift-share *** results show that:1) In the 21st century,the industrial output of three industries,namely,primary,secondary,and tertiary,and the GDP grew rapidly in the study *** tertiary industry grew the fastest;it had the largest contribution to the GDP and mean-while had become the most competitive industry in the metropolitan region.2) The development of cities within the region was not ***,compared with Tianjin,Beijing,as one of the two core cities,was more rational in the industrial ***,the surrounding eight cities,which are Shijiazhuang,Qinhuangdao,Tangshan,Langfang,Baoding,Cangzhou,Zhangjiakou,and chengde,were all uncompetitive than the two core cities.3) There was a great industrial gradient in the region(especially between the two core cities and the cities of Tangshan,Baoding,Zhangjia-kou,chengde,Cangzhou,and Langfang).As a result,it is foreseeable that the industry transfer in the Bei-jing-Tianjin-Hebei Metropolitan Region will be one of the trends in regional development,and the industry transfer is inevitably to promote the regional integration.

关键词： Beijing-Tianjin-Hebei Metropolitan Region economic growth shift-share analysis industrial structure

The characteristics of warm water inflowing and its temporal and spatial variation on the Prydz Bay continental shelf,Antarctic

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Acta Oceanologica Sinica 2016年第9期35卷 51-57页

作者： LIN Lina chen hongxia LIU Na State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Belting 100049China Key Laboratory of Marine Science and Numerical Modeling The First Institute of OceanographyState Oceanic AdministrationQingdao 266061China

Hydrographic observations collected by conductivity-temperature-depth（CTD） and instrumented elephant seals on the Prydz Bay continental shelf during 2012 and 2013 are used to characterize the intrusion of modified circumpolar deep *** a regular occurrence,modified circumpolar deep water（MCDW） intrudes onto the shelf mainly between 150–300 m layer of 73°–75°E and then turns southeast affected by the cyclonic gyre of the Prydz *** southernmost point of the warm water signal is captured on the east front of Amery Ice Shelf during March *** terms of vertical distribution,MCDW occupies the central layer of 200 m with about 100 m thickness in the austral summer,but when to winter transition,the layer of MCDW deepens with time on the central shelf.

关键词： modified circumpolar deep water the Prydz Bay continental shelf

Consistency analysis of accelerated degradation mechanism based on gray theory

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Journal of Systems Engineering and Electronics 2014年第2期25卷 322-331页

作者： Yunxia chen hongxia chen Zhou Yang Rui Kang Yi Yang School of Reliability and Systems Engineering Beihang University

A fundamental premise of an accelerated testing is that the failure mechanism under elevated and normal stress levels should remain the same. Thus, verification of the consistency of failure mechanisms is essential during an accelerated testing. A new consistency analysis method based on the gray theory is pro- posed for complex products. First of all, existing consistency ana- lysis methods are reviewed with a focus on the comparison of the differences among them. Then, the proposed consistency ana- lysis method is introduced. Two effective gray prediction models, gray dynamic model and new information and equal dimensional （NIED） model, are adapted in the proposed method. The process to determine the dimension of NIED model is also discussed, and a decision rule is expanded. Based on that, the procedure of ap- plying the new consistent analysis method is developed. Finally, a case study of the consistency analysis of a reliability enhancement testing is conducted to demonstrate and validate the proposed method.

关键词： enhancement test mechanism consistency gray the-ory smart electricity meter.

Mechanical properties of gangue-containing aluminosilicate based cementitious materials

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Journal of University of Science and Technology Beijing 2006年第2期13卷 183-189页

作者： Huajian Li Henghu Sun Xuejun Xiao hongxia chen Department of Material Science and Engineering Tsinghua University Beijing 100084 China Deportment of Resources China University of Mining ＆ Technology （Beijing） Beijing 100083 China

High performance aluminosilicate based cementitious materials were produced using calcined gangue as one of the major raw materials. The gangue was calcined at 500℃. The main constituent was calcined gangue, fly ash and slag, while alkali-silicate solutions were used as the diagenetic agent. The structure of gangue-containing aluminosilicate based cementitious materials was studied by the methods of IR, NMR and SEM. The results show that the mechanical properties are affected by the mass ratio between the gangue, slag and fly ash, the kind of activator and additional salt. For 28-day curing time, the compressive strength of the sample with a mass proportion of 2：1：1 （gangue： slag： fly ash） is 58.9 MPa, while the compressive strength of the sample containing 80wt% gangue can still be up to 52.3 MPa. The larger K^＋ favors the formation of large silicate oligomers with which AI（OH）4- prefers to bind. Therefore, in Na-K compounding activator solutions more oligomers exist which result in a stronger compressive strength of aluminosilicate-based cementitious materials than in the case of Na-containing activator. The reasons for this were found through IR and NMR analysis. Glauber＇s salt reduces the 3-day compressive strength of the paste, but increases its 7-day and 28-day compressive strengths.

关键词： gangue slag fly ash aluminosilicate based cementitious materials mechanical properties

Severe winter weather as a response to the lowest Arctic sea-ice anomalies

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Acta Oceanologica Sinica 2013年第10期32卷 11-15页

作者： chen hongxia LIU Na ZHANG Zhanhai Key Laboratory of Marine Science and Numerical Modeling First Institute of OceanographyState Oceanic Administration Key Laboratory for Polar Science Polar Research Institute of ChinaState Oceanic Administration

Possible impact of reduced Arctic sea-ice on winter severe weather in China is investigated regarding the snowstorm over southern China in January 2008. The sea-ice conditions in the summer （July-September） and fall （September-November） of 2007 show that the sea-ice is the lowest that year. During the summer and fall of 2007, sea ice displayed a significant decrease in the East Siberian, the northern Chukchi Sea, the western Beaufort Sea, the Barents Sea, and the Kara Sea. A ECHAM5.4 atmospheric general circula- tion model is forced with realistic sea-ice conditions and strong thermal responses with warmer surface air temperature and higher-than-normal heat flux associated with the sea-ice anomalies are found. The model shows remote atmospheric responses over East Asia in January 2008, which result in severe snowstorm over southern China. Strong water-vapor transported from the Bay of Bengal and from the Pacific Ocean related to Arctic sea-ice anomalies in the fall （instead of summer） of 2007 is considered as one of the main causes of the snowstorm formation.

关键词： Arctic sea ice severe winter weather ECHAM5.4 atmospheric general circulation model

Ce-promoted Mn/ZSM-5 catalysts for highly efficient decomposition of ozone

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Journal of Environmental Sciences 2021年第5期33卷 219-228页

作者： Linlin Wei hongxia chen Ying Wei Jingbo Jia Runduo Zhang State Key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Energy Environmental CatalysisBeijing University of Chemical TechnologyBeijing 100029PR China

Manganese oxides supported by ZSM-5 zeolite(Mn/ZSM-5) as well as their further modified by Ce promoter were achieved by simple impregnation method for ozone catalytic decomposition. The yCe20Mn/ZSM-5–81 catalyst with 8% Ce loading showed the highest catalytic activity at relative humidity of 50% and a space velocity of 360 L/(g × hr), giving 93% conversion of 600 ppm O_(3) after 5 hr. Moreover, this sample still maintained highly activity and stability in humid air with 50%–70% relative humidity. Series of physicochemical characterization including X-ray diffraction, temperature-programmed technology(NH_3-TPD and H_(2)-TPR), X-ray photoelectron spectroscopy and oxygen isotopic exchange were introduced to disclose the structure-performance relationship. The results indicated that moderate Si/Al ratio(81) of zeolite support was beneficial for ozone decomposition owing to the synergies of acidity and hydrophobicity. Furthermore, compared with 20 Mn/ZSM-5-81, Ce doping could enhance the amount of low valance manganese(such as Mn^(2+) and Mn^(3+)). Besides, the Ce^(3+)/Ce^(4+) ratio of 8Ce20Mn/ZSM-5-81 sample was higher than that of 4Ce_(2)0 Mn/ZSM-5-81. Additionally, the synergy between the MnO_x and CeO_(2) could easily transfer electron via the redox cycle, thus resulting in an increased reducibility at low temperatures and high concentration of surface oxygen. This study provides important insights to the utilization of porous zeolite with high surface area to disperse active component of manganese for ozone decomposition.

关键词： Manganese oxide ZSM-5 zeolite Ce promoter Adsorbed oxygen Ozone decomposition

Multi-core structure of the main part of the Kuroshio at G-PN section in the East China Sea

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Chinese Science Bulletin 2006年第6期51卷 738-746页

作者： chen hongxia YUAN Yeli HUA Feng Institute of Oceanology Chinese Academy of Sciences Qingdao266071 China First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Graduate School of Chinese Academy of Sciences Beijing 100039China

Sectional velocity distribution of the East China Sea Kuroshio is one of the basic points in the study of the Kuroshio. Hydrographic temperature and salinity data at G-PN section in the East China Sea from June 1955 to November 2001 are collected and properly processed to calculate the geostrophic cur-rent using dynamic height method at the transect of the Kuroshio. After analysis of calculation results, the basic current structure of the Kuroshio in its main part is examined together with scalar estimate and char-acters of multi- core structure, and spacial-temporal variations of current cores’ position. Main result shows that (1) single-core structure, double-core structure and multi-core structure are basic forms in axial part of the Kuroshio; (2) abvious temporal varia-tions exist in current structure of the Kuroshio; (3) the current of structure of the Kuroshio has distinctly seasonal association. The number of current cores is on the high side of core numbers in average and multi-core stucture appears in fall mostly.

关键词：黑潮中国东海日本洋流多中心结构速度分布

Tide and Current Observations in the Central Chukchi Sea During the Summer of 2012

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Journal of Ocean University of China 2016年第2期15卷 201-208页

作者： WANG Huiwu LIU Na chen hongxia College of Physical and Environmental Oceanography Ocean University of China First Institute of Oceanography State Oceanic Administration

Current data from a moored Acoustic Doppler Current Profiler （ADCP） deployed at 69°30.155N, 169″00.654″W in the central Chukchi Sea during 2012 summertime is analyzed in the present paper. Characteristics of tidal and residual currents are obtained with Cosine-Lanczos filter and cross-spectral analyses. The main achievements are as follows： 1） Along with the local inertial frequency of 12.8 h, two other peaks at -12-h and -10-d dominate the time series of raw velocity; 2） The M2 dominates the 6 resolved tide constituents with significant amplitude variations over depth and the ratios of current speed of this constituent to that of the total tidal current are 54% and 47% for u and v components, respectively. All the resolved tidal constituents rotate clockwise at depth with the exception of MM and O1. The constituents of M2 and $2 with the largest major semi-axes are similar in eccentricity and orientation at deeper levels; 3） The maximum of residual currents varies in a range of 20-30 cm s-1 over depth and the current with lower velocities flow more true north with smaller magnitudes compared to the current in surface layer. The -10d fluctuation of residual current is found throughout the water column and attributed to the response of current to the local wind forcing, with an approximate 1.4 d lag-time at the surface level and occurring several hours later in the lower layer; 4） Mean residual currents flow toward the north with the magnitudes smaller than 7 cm s-1 in a general agreement with previous studies, which suggests a relatively weaker but stable northward flow indeed exists in the central Chukchi Sea.

关键词： central Chukchi Sea tidal and residual currents local wind forcing

Industrial Spatial Agglomeration Using Distance-based Approach in Beijing, China

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Chinese Geographical Science 2015年第6期25卷 698-712页

作者： LI Jiaming ZHANG Wenzhong YU Jianhui chen hongxia Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Regional Sustainable Development Modeling Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences School of Government Central University of Finance and Economics

To study the difference of industrial location among different industries, this article is to test the spatial agglomeration across industries and firm sizes at the city level. Our research bases on a unique plant-level data set of Beijing and employs a distance-based approach, which considers space as continuous. Unlike previous studies, we set two sets of references for service and manufacturing industries respectively to adapt to the investigation in the intra-urban area. Comparing among eight types of industries and different firm sizes, we find that： 1） producer service, high-tech industries and labor-intensive manufacturing industries are more likely to cluster, whereas personal service and capital-intensive industries tend to be randomly dispersed in Beijing; 2） the spillover of the co-location of finns is more important to knowledge-intensive industries and has more significant impact on their allocation than business-oriented services in the intra-urban area; 3） the spatial agglomeration of service industries are driven by larger establishments, whereas manufac- turing industries are mixed.

关键词： distance-based approach spatial agglomeration intra-urban area Beijing