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3D modeling of deepwater turbidite lobes:a review of the research status and progress

Petroleum science 2020年第2期17卷 317-333页

作者： Lei-Fu Zhang Mao Pan Zhao-Liang Li Fault analysis Group School of Geological SciencesUniversity College DublinDublinIreland PetroChina Research Institute of Petroleum Exploration and Development BeijingChina National Energy Shale Gas Research(Experiment)center BeijingChina CNPC Key Laboratory of Unconventional Oil and Gas BeijingChina school of Earth and space science Peking UniversityBeijingChina China Aero Geophysical Survey and Remote Sensing center for Natural Resources BeijingChina

Deepwater turbidite lobe reservoirs have massive hydrocarbon potential and represent one of the most promising exploration targets for hydrocarbon *** elements of turbidite lobes internal heterogeneity include the architectural hierarchy and complex amalgamations at each hierarchical level leading to the complex distribution of shale *** to limitation of data,to build models realistically honoring the reservoir architecture provides an effective way to reduce risk and improve hydrocarbon recovery.A variety of modeling techniques on turbidite lobes exist and can be broadly grouped into pixel-based,process-based,process-oriented,surface-based,object-based and a hybrid approach of two or more of these *** rationale and working process of methods is reviewed,along with their pros and *** terms of geological realism,object-based models can capture the most realistic architectures,including the multiple hierarchy and the amalgamations at different hierarchical *** terms of data conditioning,pixel-based and multiple-point statistics methods could honor the input data to the best *** practical,dif?ferent methods should be adopted depending on the goal of the *** a review could improve the understanding of existing modeling methods on turbidite lobes and could benefit the hydrocarbon exploration activities of such reservoirs in offshore China.

关键词： Turbidite lobes Architectural hierarchy Architecture element Stochastic modeling Sand amalgamation

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Treatment of lumbar disc herniation with robot combined with unilateral biportal endoscopic technology:A case report

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World Journal of Clinical Cases 2024年第17期12卷 3235-3242页

作者： Yan-Dong Liu Duo-Fang Xu Qiang Deng Yan-Jun Zhang Tie-Feng Guo Ran-Dong Peng Jun-Jie Li graduate school Gansu University of Traditional Chinese MedicineLanzhou 730030Gansu ProvinceChina Spinal Disease Treatment center Gansu Provincial Hospital of Traditional Chinese MedicineLanzhou 730050Gansu ProvinceChina Department of Spinal Orthopedics II Gansu Provincial Hospital of Traditional Chinese MedicineLanzhou 730050Gansu ProvinceChina Department of Osteomyelitis Gansu Provincial Hospital of Traditional Chinese MedicineLanzhou 730050Gansu ProvinceChina

BACKGROUND This reported procedure combines the orthopedic surgical robot with the unilateral biportal endoscopy-lumbar interbody fusion(UBE-LIF),utilizing the UBE's wide viewing field and operating space to perform minimally invasive decompressive fusion of the lesioned segment,and the orthopedic surgical robot's intelligence and precision to perform percutaneous pedicle screw *** advancement of this procedure lies in the superposition of advantages and offsetting disadvantages of the two new technologies,and the maximum effect of treatment is achieved with maximum minimization of invasiveness and precision under the monitoring of imaging instruments to maximize the benefit of patients,and this review reports a case of multiple-segment lumbar decompression and fusion surgery for lumbar disc herniation via robot-assisted UBE for *** SUMMARY A 44-year-old patient presented to our *** various clinical data,we diagnosed the patient with lumbar disc herniation with radiculopathy,lumbar spondylolisthesis,and lumbar spinal *** developed a surgical plan of"UBE decompression+UBE-LIF+orthopedic surgery robot-assisted percutaneous pedicle screw implantation for internal fixation".The results were *** We present an extremely rare case of multiple-segment lumbar decompression and fusion surgery for lumbar disc herniation via robot-assisted UBE and achieved good ***,the technique is worthy of clinical promotion.

关键词： Orthopedic robot Unilateral biportal endoscopy Unilateral biportal endoscopic lumbar interbody fusion Lumbar disc herniation Decompression fusion Case report

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Quality assessment of onboard GPS receiver and its combination with DORIS and SLR for Haiyang 2A precise orbit determination

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science China Earth sciences 2015年第1期58卷 138-150页

作者： GUO Jing ZHAO QiLe GUO Xiang LIU XiangLin LIU JingNan ZHOU Quan GNSS Research center Wuhan University school of Geodesy and Geomatics Wuhan University Fugro Intersite B.V. Leidschendam 2263HWNetherlands Collaborative Innovation center of Earth and space science Wuhan University Test and Assessment Research center China Satellite Navigation Office

The GPS,DORIS,and SLR instruments are installed on Haiyang 2A(HY2A)altimetry satellite for Precise Orbit Determination(POD).Among these instruments,the codeless GPS receiver is the state-of-art Chinese indigenous onboard receiver,and it is the first one successfully used for Low Earth Orbit(LEO)***,the contribution assesses the performance of the receiver through an analysis of data integrity,numbers of all tracked and valid measurements as well as multipath *** receiver generally shows good performance and quality despite a few *** example,L2 observations are often missing in low elevations,particularly during the ascent of GPS satellites,and the multipath errors of P1 show a slightly abnormal ***,the PCO(Phase center Offset)and PCV(Phase center Variation)of the antenna of the GPS receiver are determined in this contribution.A significant leap for Z-component of PCO up to-1.2 cm has been found on 10 October ***,the obtained PCO and PCV maps are used for GPS only POD *** post-fit residuals of ionosphere-free phase combinations reduce almost 50%,and the radial orbit differences with respect to CNES(Centre National d’Etudes Spatiales)Precise Orbit Ephemeris(POEs)improve about 13.9%.The orbits are validated using the SLR data,and the RMS of SLR Observed minus Computed(O-C)residuals reduces from 17.5 to 15.9 *** improvements are with respect to the orbits determined without PCO and ***,six types of solutions are determined for HY2A satellite using different combinations of GPS,DORIS,and SLR *** of SLR O-C residuals and cross-comparison of orbits obtained in the contribution and the CNES POEs indicate that the radial accuracy of these orbits is at the 1.0 cm level for HY2A orbit solutions,which is much better than the scientific requirements of this *** is noticed that the GPS observations dominate the achievable accuracy of POD,and the combination of multiple types of observation

关键词： Haiyang 2A GPS receiver multipath precise orbit determination phase center offset phase center variations DORIS SLR

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Effect of the head cavity on pressure oscillation suppression characteristics in large solid rocket motors

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science China(Technological sciences) 2015年第7期58卷 1250-1262页

作者： ZHANG Qiao WANG NingFei LI JunWei SU WanXing ZHANG Yan China Academy of space Technology school of Aerospace Engineering Beijing Institute of Technology Research and Development center China Academy of Launch Vehicle Technology Qian Xue-sen Laboratory of space Technology

In order to discover the effect of head cavity on resonance damping characteristics in solid rocket motors, large-eddy simulations with wall-adapting-local-eddy-viscosity subgrid scale turbulent model are implemented to study the oscillation flow field induced by vortex shedding based on the VKI （yon Karman Institute） experimental motor. Firstly, mesh sensitivity analysis and grid-independent analysis are carried out for the computer code validation. Then, the numerical method is further validated by comparing the calculated results and experimental data. Thirdly, the effects of head-end cavity on the pressure oscillation am-plitudes are studied in this paper. The results indicate that cavity volume, location and configuration have a cooperative ef- fect on the oscillation amplitude. It is proved that Rayleigh criterion can be used as a guiding principle for the design of reso- nance damping cavity. The change of the head-end cavity breaks the balance between the mass flux and acoustic energy. Therefore, the pressure oscillation characteristics change accordingly. It is concluded that a large mass flux added at the pres- sure antinode could attribute to significant amplitude. Meanwhile, the damping effect of the cavity is stronger when the dis- tance between cavity and pressure antinode becomes shorter. Finally, this method is applied to the modification of an engi- neering solid rocket motor. The static test of solid rocket motor reflects that the oscillations can be effectively suppressed by a head-end cavity.

关键词： solid rocket motor combustion instability large eddy simulation rayleigh criterion suppression method

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Compound diffractive telescope system:design,stray light analysis,and optical test

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Chinese Physics B 2010年第1期19卷 234-240页

作者：岳巾英刘华卢振武许文斌张虎张红鑫刘英 Opto-electonics Technology center Changchun Institute of OpticsFine Mechanics and Physics graduate school of the Chinese Academy of sciences

The compound diffractive telescope is a novel space optical system which combines the structure of compound eyes with diffractive optics and so it has a lighter weight, a wider field of view （FOV）, a lower cost as well as looser fabrication tolerance. In this paper, the design of a compound diffractive telescope composed of one primary lens and twenty-one eyepieces is introduced. Then the influence of diffraction orders on the performance of the system is analysed. A modified phase function model of diffractive optics is proposed to analyse the modulation transfer function （MTF） curves for 0° FOV, which provides a more accurate prediction of the performance of the system. In addition, an optimized mechanism is also proposed to suppress stray light. The star image and resolution tests show that the system can achieve diffraction limit imaging within ±2° of FOV and 4-4 mm of eccentricity. Finally, a series of pictures of an object are taken from different channels, and the splicing of pictures from adjacent FOVs is demonstrated. In summary, the designed system has been proved to have great potential applications.

关键词： lens system design compound eyes structure diffractive lens stray light

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Small-scale ion flux and magnetic field fluctuations in solar wind, foreshock and magnetosheath

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Chinese Physics B 2007年第5期16卷 1477-1487页

作者： N. N. Shevyrev 杜艰 G. N. Z astenker 王赤 P. E. Eiges space Research Institute Russian Academy of Sciences Profsoyuznaya Street 84/32 117997 Moscow Russia Key Laboratory of space Weather Center for Space Science and Applied Research Chinese Academy of Sciences graduate school Chinese Academy of Sciences Beijing 100080 China

We have continued investigation of waves in the regions of undisturbed solar wind, foreshock and magnetosheath. The analysis of ion flux and magnetic field variations with the time interval 1-240s was performed in the regions above. Very large variation in such a time interval can be considered the common feature of the foreshock and magnetosheath. The results of case and statistical studies showed that the level of relative variations of ion flux and magnetic field magnitude in foreshock is about 3 times larger than in undisturbed solar wind. Variations of these parameters in the magnetosheath topologically connected with the quasi-parallel bow shock are about two times larger than those behind the quasi-perpendicular. We also compared the results from Interball-1 data analysis with those from statistical analysis of cluster magnetic field measurements. The magnetic field variations obtained from the different satellite data coincide with each other very well not only in quality but also in quantity.

关键词： magnetosheath foreshock solar wind

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Contribution of tropical cyclone rainfall at categories to total precipitation over the Western North Pacific from 1998 to 2007

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science China Earth sciences 2015年第11期58卷 2015-2025页

作者： CHEN FengJiao FU YunFei school of Earth and space sciences University of Science and Technology of China State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

Based on 10 years precipitation data from Tropical Rainfall Measurement Mission （TRMM） Multi-satellite Precipitation analysis （TMPA） 3B42 and the best track data from China Meteorological Administration （CMA）, the seasonal, monthly and annual contribution of tropical cyclone （TC） precipitation to the total rainfall are analyzed over the Western North Pacific （WNP） during 1998 to 2007 from May to December. The results show that：（1） TC seasonal rainfall contribution ranges from 4% in inland regions to above 40% in ocean-regions of 15°N-25°N. TCs at higher categories contribute much more to the total precipitation. （2） On monthly scale, TCs contribute 60% to the total rainfall regionally during whole TC season, which is the maximum contribution. The peak contribution of TC rainfall averaged in multi-months of the ten years occurs in August （28%） over the whole ocean impacted by TC and in December （23%） over the whole land impacted by TC, respectively. （3） On annual scale, the maximum contribution of TC precipitation to the total rainfall are in 2004 （-30%） over ocean and in 1998 （-20%） over land, respectively. （4） The contribution of TC precipitation to the total rainfall increases 6% （decreases 6%） in El Nino （La Nifia） years compared with neutral years.

关键词： tropical cyclone precipitation contribution 3B42 WNP ENSO

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Dynamic Shortest Path Monitoring in Spatial Networks

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Journal of Computer science & Technology 2016年第4期31卷 637-648页

作者： Shuo Shang Lisi Chen Zhe-Wei Wei Dan-Huai Guo Ji-Rong Wen State Key Laboratory of Software Development Environment Beijing 100191 China Department of Computer science China University of Petroleum Beijing 102249 China school of Computer Engineering Nanyang Technological University Singapore 639798 Singapore Beijing Key Laboratory of Big-data Management and analysis Methods Renmin University of China Beijing 100080 China Computer Network Information center Chinese Academy of Sciences Beijing 100190 China

With the increasing availability of real-time traffic information, dynamic spatial networks are pervasive nowa- days and path planning in dynamic spatial networks becomes an important issue. In this light, we propose and investigate a novel problem of dynamically monitoring shortest paths in spatial networks （DSPM query）. When a traveler aims to a des- tination, his/her shortest path to the destination may change due to two reasons： 1） the travel costs of some edges have been updated and 2） the traveler deviates from the pre-planned path. Our target is to accelerate the shortest path computing in dynamic spatial networks, and we believe that this study may be useful in many mobile applications, such as route planning and recommendation, car navigation and tracking, and location-based services in general. This problem is challenging due to two reasons： 1） how to maintain and reuse the existing computation results to accelerate the following computations, and 2） how to prune the search space effectively. To overcome these challenges, filter-and-refinement paradigm is adopted. We maintain an expansion tree and define a pair of upper and lower bounds to prune the search space. A series of optimization techniques are developed to accelerate the shortest path computing. The performance of the developed methods is studied in extensive experiments based on real spatial data.

关键词： shortest path dynamic spatial network spatial database location-based service

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Acceptance on colorectal cancer screening upper age limit in South Korea

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World Journal of Gastroenterology 2020年第27期26卷 3963-3974页

作者： Xuan Quy Luu Kyeongmin Lee Yun Yeong Lee Mina Suh Yeol Kim Kui Son Choi graduate school of Cancer science and Policy National Cancer CenterGoyang-si 10408South Korea National Cancer Control Institute National Cancer CenterGoyang-si 10408South Korea

BACKGROUND The Korea National Cancer Screening Program currently provides screening for colorectal cancer(CRC)for adults older than 50 years with no upper age *** general,people are likely to only pay attention to the benefits of cancer screening and to neglect its *** consider the benefits of cancer screening as being far greater than the risks and are unaware that any potential benefits and harms can vary with *** To report acceptance of an upper age limit for CRC screening and factors associated therewith among cancer-free individuals in *** The present study analyzed data from the Korea National Cancer Screening Survey 2017,a nationally representative random sample of 4500 Korean individuals targeted for screening for the five most common types of cancer.A total of 1922 participants were included in the final *** baseline characteristics of the study population are presented as unweighted numbers and weighted *** univariate and multivariate logistic regression models were developed to examine factors related with acceptance of an upper age limit for CRC screening;subgroup analysis was also *** About 80%(1554/1922)of the respondents agreed that CRC screening should not be offered for individuals older than 80 ***,those who had never been screened for CRC had the highest acceptance rate(91%).Overall,screening history for CRC[screened by both fecal occult blood test and colonoscopy,adjusted odds ratio(aOR)=0.33,95%CI:0.22-0.50]and other cancers(aOR=0.55,95%CI:0.34-0.87),as well as a family history of cancer(aOR=0.66,95%CI:0.50-0.87),were negatively associated with acceptance of an upper age limit for CRC *** contrast,metropolitan residents(aOR=1.86,95%CI:1.29-2.68)and people who exercised regularly(aOR=1.42,95%CI:1.07-1.89)were more likely to accept an upper age *** subgrouping,we found gender,marital status,and lifetime smoking history among never-screened individuals and r

关键词： Colorectal cancer Cancer early detection Mass screening Patient participation Elderly Patients dropouts

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High-Precision Fast Direction-of-Arrival Estimation Method for Planar Array

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space(science & Technology) 2023年第1期3卷 150-153页

作者： Shuai Li Lei Li Bo Liu Yihao Song Ming Li Jie Ren Wenting Jiang Institute of Telecommunication and Navigation Satellites China Academy of Space TechnologyBeijing 100094China Innovation center of Satellite Communication System CNSABeijing 100094China school of science and Engineering The Chinese University of Hong KongShenzhenand Shenzhen Research Institute of Big DataShenzhen 518172China

The multiple signal classification method for direction-of-arrival estimation is widely applied in practical ***,the multiple signal classification method with planar array requires 2-dimensional on-grid spectrum searches,which would lead to the grid mismatch and high computational ***,a high-precision fast direction-of-arrival estimation method for planar array is *** the proposed method,a 2-stage grid search approach over the 2-dimensional spectrum is firstly applied to obtain a quick coarse estimation of direction of ***,the estimation of higher precision is achieved via a quadratic surface fitting *** results verified the effectiveness of the proposed method.

关键词： complexity estimation planar

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