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Computer Modeling in Engineering & Sciences 2022年第8期132卷 451-469页

作者： Jun zou Haolei Mou College of Safety Science and Engineering Civil Aviation University of ChinaTianjin300300China

The integration of topology optimization(TO)and additive manufacturing(AM)technologies can create significant synergy benefits,while the lack of AM-friendly TO algorithms is a serious bottleneck for the application of TO in *** this paper,a TO method is proposed to design self-supporting structures with an explicit continuous self-supporting constraint,which can be adaptively activated and tightened during the optimization *** TO procedure is suitable for various critical overhang angles(COA),which is integrated with build direction assignment to reduce performance ***,a triangular directional self-supporting constraint sensitivity filter is devised to promote the downward evolution of structures and maintain *** numerical examples are presented;all the test cases have successfully converged and the optimized solutions demonstrate good *** the meanwhile,a fully self-supporting design can be obtained with a slight cost in performance through combination with build direction assignment.

关键词： Topology optimization additive manufacturing self-supporting constraint build direction assignment gradual evolution

Three-step semiquantum secure direct communication protocol

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Science China(Physics,Mechanics & Astronomy) 2014年第9期57卷 1696-1702页

作者： zou XiangFu QIU DaoWen Department of Computer Science Sun Yat-sen University School of Mathematics and Computational Science Wuyi University Department of Computer Science and Engineering the Chinese University of Hong Kong SQIG–Instituto de Telecomunicacoes Departamento de Matem'atica Instituto Superior TecnicoUniversidade de Lisboa

Quantum secure direct communication is the direct communication of secret messages without need for establishing a shared secret key *** the existing schemes,quantum secure direct communication is possible only when both parties are *** this paper,we construct a three-step semiquantum secure direct communication(SQSDC)protocol based on single photon sources in which the sender Alice is *** a semiquantum protocol,a person is termed classical if he(she)can measure,prepare and send quantum states only with the fixed orthogonal quantum basis{|0,|1}.The security of the proposed SQSDC protocol is guaranteed by the complete robustness of semiquantum key distribution protocols and the unconditional security of classical one-time pad ***,the proposed SQSDC protocol is also completely *** robustness indicates that nonzero information acquired by an eavesdropper Eve on the secret message implies the nonzero probability that the legitimate participants can find errors on the bits tested by this *** the proposed protocol,we suggest a method to check Eves disturbing in the doves returning phase such that Alice does not need to announce publicly any position or their coded bits value after the photons transmission is ***,the proposed SQSDC protocol can be implemented with the existing *** with many quantum secure direct communication protocols,the proposed SQSDC protocol has two merits:firstly the sender only needs classical capabilities;secondly to check Eves disturbing after the transmission of quantum states,no additional classical information is needed.

关键词： quantum secure direct communication semiquantum complete robustness security

Bilateral self-amalgamation of a Heegaard splitting and Hempel distance

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Science China Mathematics 2015年第7期58卷 1499-1510页

作者： zou YanQing LIU XiMin School of Mathematical Sciences Dalian University of Technology

A closed orientable Haken 3-manifold containing a non separating incompressible closed surface has two canonical Heegaard splittings, which are called self-amalgamation and bilateral *** distance introduced by Hempel is a useful index in studying Heegaard splitting. This paper studies the stabilization problem for the bilateral self-amalgamation, and proves that if the distance of bilateral selfamalgamation of a Heegaard splitting is at least 9, then it is unstabilized, weakly reducible and irreducible.

关键词： stabilization Heegaard distance subsurface projection

Variations of sea ice in the Antarctic and Arctic from 1997-2006

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Frontiers of Earth Science 2014年第3期8卷 385-392页

作者： Huijie DONG Xiaolei zou College of Atmospheric Science Nanjing University of Information Science & Technology Nanjing 210044 China Department of Earth Ocean & Atmospheric Science Florida State University Tallahassee 32304 USA

Sea ice in polar areas is an important part of the global climate system. In order to obtain variations in sea ice extent for the Antarctic and Arctic, this paper analyzed the Special Sensor Microwave/Imager （SSM/I） sea ice data product dating from March 1, 1997 to December 31, 2006. During this period, the sea Antarctic with the trend ice extent increased in the of （0.5467±0.4933）× 10^4 ***^-1, and decreased in the Arctic with the trend of （-7.6125±0.3503）× 10^4 ***^-1. In different sectors of the Antarctic, variations of the sea ice extent are different. The sea ice extent increased in the Weddell Sea and Indian Ocean, but decreased in the Ross Sea, Western Pacific Ocean, and Bellingshausen/Amundsen Seas.

关键词： sea ice concentration (SICN) sea ice extent,linear trend

Development and evaluation of a regional ocean-atmosphere coupled model with focus on the western North Pacific summer monsoon simulation:Impacts of different atmospheric components

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Science China Earth Sciences 2012年第5期55卷 802-815页

作者： zou LiWei ZHOU TianJun LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

A regional ocean atmosphere coupled model (ROAM) is developed through coupler OASIS3,and is composed of regional climate model RegCM3 and CREM (Climate version of Regional Eta Model) as its atmospheric component and of a revised Princeton ocean model (POM2000) as its oceanic *** performance of the ROAM over the western North Pacific summer monsoon region is assessed by the case simulation of warm season in *** of different atmospheric model components on the performance of ROAM are *** with stand-alone simulation,CREM (RegCM3) produces more (or less) rainfall over ocean area with inclusion of the air-sea *** biases of rainfall are caused by the different biases of SST derived from the coupled *** (or cold) SST bias simulated by CREM_CPL (RegCM3_CPL) increases (or decreases) the evaporation at sea surface,then increases (or decreases) the rainfall over *** analyses suggest that the biases of vertical profile of temperature and specific humidity in stand-alone simulations may be responsible for the SST biases in regional coupled *** with reanalysis data,the warmer (or colder) and moister (or dryer) lower troposphere simulated in CREM (RegCM3) produces less (or more) sea surface latent heat ***,the more unstable (or stable) lower troposphere produces less (or more) cloudiness at low-level,which increases (or decreases) the solar radiation reaching on the sea *** (RegCM3) forced by observed SST overestimates (or underestimates) the sea surface net heat flux,implying a potential warm (or cold) heat *** coupling with POM2000,the warm (or cold) heat source would further increase (or decrease) the *** biases of vertical profile of temperature and specific humidity may be ascribed to the different representation of cumulus convection in atmospheric models.

关键词： inter-comparison of regional coupling different atmospheric component western North Pacific summer monsoon model biases

Improved generalized cell mapping for global analysis of dynamical systems

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Science China(Technological Sciences) 2009年第3期52卷 787-800页

作者： HaiLin zou JianXue Xu Institute of Nonlinear Dynamics School of Aerospace Xi’an Jiaotong University Xi’an 710049 China

Three main parts of generalized cell mapping are improved for global analysis. A simple method, which is not based on the theory of digraphs, is presented to locate complete self-cycling sets that corre- spond to attractors and unstable invariant sets involving saddle, unstable periodic orbit and chaotic saddle. Refinement for complete self-cycling sets is developed to locate attractors and unstable in- variant sets with high degree of accuracy, which can start with a coarse cell structure. A nonuniformly interior-and-boundary sampling technique is used to make the refinement robust. For homeomorphic dissipative dynamical systems, a controlled boundary sampling technique is presented to make gen- eralized cell mapping method with refinement extremely accurate to obtain invariant sets. Recursive laws of group absorption probability and expected absorption time are introduced into generalized cell mapping, and then an optimal order for quantitative analysis of transient cells is established, which leads to the minimal computational work. The improved method is applied to four examples to show its effectiveness in global analysis of dynamical systems.

关键词： global analysis generalized cell mapping invariant set chaotic saddle crisis

Strong convergence results for hemivariational inequalities

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Science China Mathematics 2006年第7期49卷 893-901页

作者： LIU Zhenhai zou Jiezhong Department of Mathematics Changsha University of Science and Technology Changsha 410076 China School of Mathematical Science and Computing Technology Central South University Changsha 410075 China School of Mathematical Science and Computing Technology Central South University Changsha 410075 China

The purpose of this paper is to study a regularization method of solutions of ill-posed problems involving hemivariational inequalities in Banach spaces. Under the assumption that the hemivariational inequality is solvable, a strongly convergent approximation procedure is designed by means of the so-called Browder-Tikhonov regularization method. Our results generalize and extend the previously known theorems.

关键词： hemivariational inequalities, Clarke subdifferential, regularization, strong convergence.

Impact of FY-3A MWTS radiances on prediction in GRAPES with comparison of two quality control schemes

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Frontiers of Earth Science 2014年第2期8卷 251-263页

作者： Juan LI Xiaolei zou National Meteorological Center China Meteorological Administration Beijing 100081 China Department of Earth Ocean and Atmospheric Sciences Florida State University Tallahassee 32306 USA

The impact of Microwave Temperature Sounder （MWTS） radiances on the prediction of the Chinese Numerical Weather prediction （NWP） system-GRAPES （Global and Regional Assimilation and PrEdiction System） with comparison of two Quality Control （QC） schemes was researched. The main differences between the two schemes are cloud detection, O-B （brightness temperature difference between observation and model simulation） check and thinning. To evaluate the impact of the two QC schemes on GRAPES, a typhoon case study and cycle experiments were conducted. In the typhoon case study, two experiments were conducted using both the new and old QC schemes. The results show that outliers are removed in the new QC while they exist in the old QC. The analysis and the model forecast are subsequently generated after assimilating data from the two QC schemes. The model-predicted steering flows more southward with the new QC scheme, and as a result, the forecast track in the experiments is more southward, i.e., closer to the best track than the old scheme. In addition to the case study, four impact cycle experiments were conducted for 25-day periods. The results show that the new QC scheme removed nearly all the biases whereas the old scheme could not. Furthermore, the mean and standard deviation of analysis increments with the new scheme is much smaller than those of O-B. In contrast, the old scheme values are either slightly smaller or the same. Verifications indicate that forecast skill is improved after applying the new scheme. The largest improvements are found in the Southern Hemisphere. According to the results above, MWTS with the new QC scheme can improve the GRAPES forecast.

关键词： FY-3 MWTS typhoon GRAPES

Asian Summer Monsoon Onset in Simulations and CMIP5 Projections Using Four Chinese Climate Models

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Advances in Atmospheric Sciences 2015年第6期32卷 794-806页

作者： zou Liwei ZHOU Tianjun State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences

The reproducibility and future changes of the onset of the Asian summer monsoon were analyzed based on the simulations and projections under the Representative Concentration Pathways （RCP） scenario in which anthropogenic emissions continue to rise throughout the 21 st century （i.e. RCP8.5） by all realizations from four Chinese models that participated in the Coupled Model Intercomparison Project Phase 5 （CMIP5）. Delayed onset of the monsoon over the Arabian Sea was evident in all simulations for present-day climate, which was associated with a too weak simulation of the low-level Somali jet in May. A consistent advanced onset of the monsoon was found only over the Arabian Sea in the projections, where the advanced onset of the monsoon was accompanied by an increase of rainfall and an anomalous anticyclone over the northern Indian Ocean. In all the models except FGOALS-g2, the enhanced low-level Somali jet transported more water vapor to the Arabian Sea, whereas in FGOALS-g2 the enhanced rainfall was determined more by the increased wind convergence. Furthermore, and again in all models except FGOALS-g2, the equatorial SST warming, with maximum increase over the eastern Pacific, enhanced convection in the central West Pacific and reduced convection over the eastern Indian Ocean and Maritime Continent region, which drove the anomalous anticyclonic circulation over the western Indian Ocean. In contrast, in FGOALS-g2, there was minimal （near-zero） warming of projected SST in the central equatorial Pacific, with decreased convection in the central West Pacific and enhanced convection over the Maritime Continent. The broader-scale differences among the models across the Pacific were related to both the differences in the projected SST pattern and in the present-day simulations.

关键词： Asian summer monsoon onset climate projection Chinese climate models

Changes in Regional Heavy Rainfall Events in China during 1961–2012

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Advances in Atmospheric Sciences 2015年第5期32卷 704-714页

作者： zou Xukai REN Fumin National Climate Center State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Jiangsu Collaborative Innovation Center for Climate Change

A new technique for identifying regional climate events, the Objective Identification Technique for Regional Extreme Events（OITREE）, was applied to investigate the characteristics of regional heavy rainfall events in China during the period1961–2012. In total, 373 regional heavy rainfall events（RHREs） were identified during the past 52 years. The East Asian summer monsoon（EASM） had an important influence on the annual variations of China＇s RHRE activities, with a significant relationship between the intensity of the RHREs and the intensity of the Mei-yu. Although the increase in the frequency of those RHREs was not significant, China experienced more severe and extreme regional rainfall events in the 1990 s. The middle and lower reaches of the Yangtze River and the northern part of South China were the regions in the country most susceptible to extreme precipitation events. Some stations showed significant increasing trends in the southern part of the middle and lower reaches of the Yangtze River and the northern part of South China, while parts of North China, regions between Guangxi and Guangdong, and northern Sichuan showed decreasing trends in the accumulated intensity of *** spatial distribution of the linear trends of events＇ accumulated intensity displayed a similar so-called ＂southern flooding and northern drought＂ pattern over eastern China in recent decades.

关键词： China regional heavy rainfall events