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Development of An Ionospheric Scintillation Monitor Using Single Frequency GPS Receiver

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Wuhan University Journal of Natural Sciences 2002年第2期7卷 189-194页

作者： Shu Di-fei xu ji-sheng School of Electronic Information Wuhan UniversityWuhan 430072HubeiChina

Besides their intended use in radio navigation, global positioning system (GPS) satellite signals provide convenient radio beacons for ionospheric studies. Among other propagation phenomena, the ionosphere affects GPS signal propagation through amplitude scintillations that develop after radio waves propagation through ionospheric electron density irregularities. This paper outlines the design, testing, and results of a specialized GPS receiver to monitorL-band scintillations. The scintillation monitor system consists of a commercial GPS receiver development kit with its software designed to log signal strength and carrier phase from up to 12 channels at one sample per second rate. Other prime features of the monitor include the data compression transmission and processing. Here is the fact that they are inexpensive and compact and therefore can be readily proliferated.

关键词： global positioning system ionosphere scintillation irregularity

Clinical experience of surgical intervention for severe acute pancreatitis

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Chinese Medical Journal 2014年第11期127卷 2097-2100页

作者： xu Yuan Shao Qinshu Yang jin Yu Xiaojun xu ji Department of Gastrointestinal Surgery Zhejiang Provincial People'sHospital Hangzhou Zhejiang 310014 China

Background The controversy on the treatment strategy for severe acute pancreatitis （SAP） has never stopped for the past *** now surgical procedures play a decisive role in the treatment of SAP,especially in managing the related complications,but the rational indications,timing,and approaches of surgical intervention for SAP are still *** Clinical data of 308 SAP patients recruited during January 2000-January 2013,including 96 conservatively treated cases plus 212 surgically intervened cases,were comparatively *** on the initial surgical intervention time,the surgical intervention group was split into two：early intervention group （within 2 weeks） 103 cases,and late intervention group （after 2 weeks） 109 *** In the conservative treatment group,the cure rate was 82.29% （79/96）,the death rate was 13.54% （13/96）,and 4 cases self-discharged,while in the surgical intervention group,the cure rate was 84.43% （179/212） and the death rate was 10.85% （23/212） with 10 cases *** difference was of no statistical significance between these two groups （P 〉0.05）.In surgical intervention group,the death rate 15.53% （16/103） in the early surgical intervention group was higher than that of late surgical intervention group 6.42% （7/109）,and the difference was statistically significant （P 〈0.05）.Conclusions Both conservative treatment and surgical intervention play important roles in the treatment of SAP,and the indication,timing,and procedure should be strictly *** earlier than 2 weeks after onset of the disease is not recommended in patients with necrotizing pancreatitis only when there are specific indications,such as multiple organ failure,which does not improve despite active treatment,and in those who develop abdominal compartment syndrome.

关键词： severe acute pancreatitis surgical intervention timing and procedure

Mobile-Customer Identity Recognition

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Wuhan University Journal of Natural Sciences 2005年第6期10卷 1013-1018页

作者： LI Zhan xu ji-sheng xu Min SUN Hong School of Electronic Information Wuhan University Wuhan 430072 Hubei China Department of Electronic Information Huazhong University of Science and Technology Wuhan 430074 Hubei China

By utilizing artificial intelligence and pattern rec ognition techniques, we propose an integrated mobile-customer identity recognition approach in this paper, based on cus tomer＇s behavior characteristics extracted from the customer information database. To verify the effectiveness of this approach, a test has been run on the dataset consisting of 1 000 customers in 3 consecutive *** result is compared with the real dataset in the fourth month consisting of 162 customers, which has been set as the customers for recognition. The high correct rate of the test （96.30%）, together with 1. 87% of the judge-by-mistake rate and 7.82% of the leaving-out rate, demonstrates the effectiveness of this approach.

关键词： customer identity recognition genetic algorithms fuzzy set

Interaction of straight chain alcohol vapors with self-assembled MOF film by surface plasmon resonance sensing and imaging

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Chinese Chemical Letters 2013年第7期24卷 651-653页

作者： Jun Chen ji-Ying xu Yi Chen Key Lab of Analytical Chemistry for Living Biosystems Institute of ChemistryChinese Academy of Sciences Beijing National Laboratory of Molecular Science

Interaction of straight chain alcohol vapors with MOF-199-functionalized films was studied by SPR. The signals had linear relationships with the concentration of alcohols over a wide range from 0 to 70% （v/v） and we... 详细信息

关键词： Layer by layer self-assemble of MOF Oriented growth Alcohol vapors detection Surface plasmon resonance or SPR

A transient single particle model under FCI conditions

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Nuclear Science and Techniques 2005年第5期16卷 315-320页

作者： LI Xiao-Yan SHANG Zhi xu ji-Jun Department of Nuclear Science and System Engineering School of Mechanics and Power Shanghai Jiaotong University Shanghai 200030

The paper is focused on the coupling effect between film boiling heat transfer and evaporation drag around a hot-particle in cold liquid. Based on the continuity, momentum and energy equations of the vapor film, a transient two-dimensional single particle model has been established. This paper contains a detailed description of HPMC (High-temperature Particle Moving in Coolant) model for studying some aspects of the premixing stage of fuel-coolant interactions (FCIs). The transient process of high-temperature particles moving in coolant can be simu-lated. Comparisons between the experiment results and the calculations using HPMC model demonstrate that HPMC model achieves a good agreement in predicting the time-varying characteristic of high-temperature spheres moving in coolant.

关键词： FCI 热物理学瞬时模型热力工程

Key factors in chaperonin-assisted protein folding

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Particuology 2012年第1期10卷 105-116页

作者： Ying Ren jian Gao ji xu Wei Ge jinghai Li State Key Laboratory of Multiphase Complex System Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China Graduate University of the Chinese Academy of Sciences Beijing 100039 China

Incorrect folding of proteins in the macromolecular crowding environment in living cells would cause cellular disasters. All cells have developed their structurally and functionally distinct classes of molecular chaperones to help normative proteins fold to their native structures, one of which is the most studied GroELIES complex. In the present article, large-scale all-atom explicit solvent molecular dynamics （MD） simulations have been carried out on rhodanese folding in a series of chaperonin mutants for 200ns to understand the mechanism therein. In accordance with experimental results, two factors have been identified to play a significant role, the geometrical confinement effect of the folding cavity and the charge effect of the inner surface of the cavity. Our analysis of the properties during simulation suggests that the GroEL/ES complex directly exerts force on the contacting residues of the substrate, thus assists substrate folding.

关键词： Molecular dynamics simulationExplicit solventChaperoninProtein folding

Numerical analysis of enhanced mixing in a Gallay tote blender

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Particuology 2016年第6期14卷 95-102页

作者： Xinxin Ren Guangzheng Zhou ji xu Lijie Cui Wei Ge State Key Laboratory of Multiphase Complex Systems Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China School of Chemistry and Chemical Engineering University of Chinese Academy of Sciences Beijing 100049 China

The mixing performance of a multi-bladed baffle inserted into a traditional Gallay tote blender is explored by graphic processing unit-based discrete element method software. The mixing patterns and rates are investigated for a binary mixture, represented by two different colors, under several loading profiles. The baffle effectively enhances the convective mixing both in the axial and radial directions, because of the disturbance it causes to the initial flowing layer and solid-body zone, compared with a blender without a baffle. The axial mixing rate is affected by the gap between the baffle and the wall on the left and right sides, and an optimal blade length corresponds to the maximum mixing rate. However, the radial mixing rate increases with the blade length almost monotonically.

关键词： Powder mixing Tote blender Granular materials Discrete element method Simulation Baffle

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平原M5.5地震土壤气地球化学特征及成因

地震地质 2024年第2期46卷 433-448页

作者：苏淑娟陈其峰孙豪刘军冯梁乐徐继龙杨彦明雒昆利山东省地震局济南250000 中国科学院地理科学与资源研究所北京100101 内蒙古自治区地震局呼和浩特010010 中国地震局地质研究所地震动力学国家重点实验室北京100029

2023年8月6日2时33分,山东省德州市平原县发生M5.5地震。文中跨震中布设4条长30km的勘测线,现场测量了土壤气Rn、CO_(2)和Hg浓度。结果表明:1)土壤气浓度表现出明显的空间差异,震中区与4条测线的东、西两端气体浓度相对较高。2)土壤气... 详细信息

2023年8月6日2时33分,山东省德州市平原县发生M5.5地震。文中跨震中布设4条长30km的勘测线,现场测量了土壤气Rn、CO_(2)和Hg浓度。结果表明:1)土壤气浓度表现出明显的空间差异,震中区与4条测线的东、西两端气体浓度相对较高。2)土壤气浓度的空间分布特征在震中及其东部地区相似,但在震中西部差异较大,在西部旧城断裂(F_(3))附近,Rn和CO_(2)的浓度高于震中区,推测应与地震活动和F_(3)控制的鼻状构造有关。3)Rn、CO_(2)和Hg的浓度在陵县-冠县断裂(F_(1))和F_(3)附近出现高值异常,余震自F_(1)向F_(3)发展,结合地质与地球物理研究资料推断,平原M5.5地震应与F_(1)和F_(3)共同作用有关。以上结果表明,气体地球化学方法能较好地指示隐伏断层的位置与展布方向。

关键词：平原M5.5地震断层土壤气浓度陵县-冠县断裂旧城断裂构造地球化学

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电网架空输电线路绝缘子缺陷识别算法研究

自动化仪表 2024年第7期45卷 70-74页

作者：季旭梁岩涛张剑伟国家电网有限公司北京100000 国网甘肃省电力有限公司建设分公司甘肃兰州730000

电网架空输电线路绝缘子长期处于外部暴露环境中,易产生侵蚀、开裂、破碎等问题,导致电网运行的可靠性降低。为此,对电网架空输电线路绝缘子缺陷识别算法进行了研究。通过滤波去除采集的绝缘子图像乘性噪声,利用不同尺度高斯掩膜进行卷... 详细信息

电网架空输电线路绝缘子长期处于外部暴露环境中,易产生侵蚀、开裂、破碎等问题,导致电网运行的可靠性降低。为此,对电网架空输电线路绝缘子缺陷识别算法进行了研究。通过滤波去除采集的绝缘子图像乘性噪声,利用不同尺度高斯掩膜进行卷积处理,并结合图像梯度方向提取表面缺陷特征。将构建的深度前馈神经网络作为基本架构,设置三层网络结构的自编码器。在前馈网络的优化目标函数中融入惩罚因子,以构建稀疏性限制条件。通过遗传算法优化自编码器初始权值,经网络迭代得到表面缺陷识别结果。试验结果表明,所提算法对绝缘子缺陷的识别准确率始终高于90%、平均识别用时为1.72 s,具有显著的可行性。该研究对监控安防、图像分析等领域具有一定的启示意义。

关键词：电网架空输电线路深度学习绝缘子高斯掩膜自编码器缺陷识别