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FAST ACOUSTIC IMAGING FOR A 3D PENETRABLE OBJECT IMMERSED IN A SHALLOW WATER WAVEGUIDE＊

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Journal of Computational Mathematics 2013年第5期31卷 449-469页

作者： ju qiu Zhongbo Zhang Wenfeng Pan Mathematical School Jilin University Changchun 130000 China zhongbozhang@jlu edu. cn School of Science Wuhan University of Technology Wuhan 430070 China

The paper is concerned with the inverse problem for reconstructing a 3D penetrable ob- ject in a shallow water waveguide from the far-field data of the scattered fields with many acoustic point source incidences. An indicator sampling method is analyzed and presented for fast imaging the size, shape and location of such a penetrable object. The method has the advantages that a priori knowledge is avoided for the geometrical and material proper- ties of the penetrable obstacle and the much complicated iterative techniques are avoided during the inversion. Numerical examples are given of successful shape reconstructions for several 3D penetrable obstacles having a variety of shapes. In particular, numerical results show that the proposed method is able to produce a good reconstruction of the size, shape and location of the penetrable target even for the case where the incident and observation points are restricted to some limited apertures.

关键词： Oceanic waveguide Penetrable object Inverse problems Indicator samplingmethod.

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身体活动与执行功能领域研究主题的动态演化

中国组织工程研究 2025年第14期29卷 3043-3050页

作者：邓青邱晨王庆军黄贵张业廷南京师范大学体育科学学院江苏省南京市210012 南京晓庄学院体育学院江苏省南京市211171 南京师范大学新闻与传播学院江苏省南京市210012 中国民用航空飞行学院航空安全保卫学院四川省广汉市618307

背景:身体活动与执行功能领域的相关研究不断涌现,目前尚未有学者使用可视化工具探讨这一领域研究主题的动态演化路径。目的:通过文献计量学方法,探究身体活动与执行功能领域研究主题的动态演化过程,从而理清其发展状态及知识结构的变... 详细信息

背景:身体活动与执行功能领域的相关研究不断涌现,目前尚未有学者使用可视化工具探讨这一领域研究主题的动态演化路径。目的:通过文献计量学方法,探究身体活动与执行功能领域研究主题的动态演化过程,从而理清其发展状态及知识结构的变化。方法:通过检索式:TS=(“Physical activity”AND“Executive function*”)OR TS=(Exercise AND“Executive function*”)检索Web of Science数据库,依照纳入排除标准选取4386篇相关文献为研究内容,利用SciMAT软件进行可视化分析。结果与结论:身体活动与执行功能领域的研究呈现蓬勃发展态势,相关研究日趋深入,未来发展空间较大;该领域可分为执行功能、儿童、老年人和干预措施4个方向,并形成了11条主要演化路径;“运动技能”“生活方式”“有氧运动”和“干预措施”等主题可能是未来的研究重点,“青少年”和“老年人”群体是该领域研究的重点关注人群。

关键词：身体活动执行功能认知 SciMAT 可视化分析动态演化

Exclusion of interspecific competition reduces scatter-hoarding of Siberian chipmunk Tamias sibiricus:A field study

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Integrative Zoology 2020年第2期15卷 127-134页

作者： Yinhua deng Mengyao ju Xianfeng YI College of Life Sciences Jiangxi Normal UniversityNanchangChina College of Life Sciences Qufu Normal UniversityQufuChina

Although food availability and the abundance of seed predators have been postulated to affect seed dispersal,it is not clear how seed-eating animals modify their scatter-hoarding strategies in response to different levels of interspecific *** placed paired germinated and ungerminated acorns of Quercus mongolica on 30-cm high platforms to exclude potential interspecific competition of the predominant larder hoarders Apodemus peninsulae and Myodes rufocanus,to investigate seed dispersal by a predominant scatter-hoarder,Tamias sibiricus,in the field in north-eastern *** results showed that *** ate more acorns in situ in the absence of interspecific *** the presence of interspecific competition of *** and ***,however,more acorns were scatter-hoarded by *** of interspecific competition,germination of acorns showed no significant effects on seed dispersal patterns,inconsistent with the“seed perishability hypothesis”that animals avoid hoarding seeds with high *** of interspecific competition,though relatively increasing the per capita seed abundance,appears to reduce seed dispersal,scatter-hoarding and seedling ***,we propose that moderate interspecific competition rather than competition exclusion may benefit seed scatter-hoarding and seedling establishment.

关键词： interspecific competition Quercus mongolica. seed dispersal seed perishability Tamias sibiricus

Completeness of the system {z^(λ_n)}in L^2[B,α_0]

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Acta Mathematica Sinica,English Series 2008年第12期24卷 2101-2110页

作者： ju Hong NING Guan Tie deng Department of Mathematics Jiangxi Normal University Nanchang 330022 P. R. China School of Mathematical Sciences Beijing Normal University Beijing 100875 P. R. China

Let B be an unbounded domain located outside an angle domain with vertex at the origin, A ={λn}（n = 1,2,...） be a sequence of complex numbers satisfying sup ｜ arg（λn）｜〈 α 〈 π/2 and denote by M（∧） = {z^λ, λ ∈ ∧} the corresponding system of functions z^λ（λ∈∧）. Let α0（z） be a weight function defined on B. We obtain a completeness theorem for the system M（∧） in the Hilbert space L^2 [B, α0].

关键词： completeness unbounded domain Hilbert space

Environmental stress level evaluation approach based on physical model and interval grey association degree

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Chinese Journal of Aeronautics 2013年第2期26卷 456-462页

作者： deng Guanqian qiu Jing Liu Guanjun Lv Kehong Laboratory of Science and Technology on Integrated Logistics Support College of Mechatronics Engineering and Automation National University of Defense Technology

Associating environmental stresses （ESs） with built-in test （BIT） output is an important means to help diagnose intermittent faults （IFs）. Aiming at low efficiency in association of traditional time stress measurement device （TSMD）, an association model is built. Thereafter, a novel approach is given to evaluate the integrated environmental stress （IES） level. Firstly, the selection principle and approach of main environmental stresses （MESs） and key characteristic parameters （KCPs） are presented based on fault mode, mechanism, and ESs analysis （FMMEA）. Secondly, reference stress events （RSEs） are constructed by dividing IES into three stress levels according to its impact on faults; and then the association model between integrated environmental stress event （IESE） and BIT output is built. Thirdly, an interval grey association approach to evaluate IES level is proposed due to the interval number of IES value. Consequently, the association output can be obtained as well. Finally, a case study is presented to demonstrate the proposed approach. Results show the proposed model and approach are effective and feasible. This approach can be used to guide ESs measure, record, and association. It is well suited for on-line assistant diagnosis of faults, especially IFs.

关键词： Environmental stress False alarms Intermittent faults Interval grey association degree Interval number

A discrete event systems approach to discriminating intermittent from permanent faults

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Chinese Journal of Aeronautics 2014年第2期27卷 390-396页

作者： deng Guanqian qiu Jing Liu Guanjun Lyu Kehong Laboratory of Science and Technology on Integrated Logistics Support College of Mechatronics and AutomationNational University of Defense Technology

Almost all work on model-based diagnosis （MBD） potentially presumes faults are per- sistent and does not take intermittent faults （IFs） into account. Therefore, it is common for diag- nosis systems to misjudge IFs as permanent faults （PFs）, which are the major cause of the problems of false alarms, cannot duplication and no fault found in aircraft avionics. To address this problem, a new fault model which includes PFs and IFs is presented based on discrete event systems （DESs）. Thereafter, an approach is given to discriminate between PFs and IFs by diagnosing the current fault. In this paper, the regulations of （PFs and IFs） fault evolution through fault and reset events along the traces of system are studied, and then label propagation function is modified to account for PFs and the dynamic behavior of IFs and diagnosability of PFs and IFs are defined. Finally, illustrative examples are presented to demonstrate the proposed approach, and the analysis results show the fault types can be discriminated within bounded delay if the system is diagnosable.

关键词： Diagnosability Diagnoser Discrete event systemsFault diagnosis Intermittent faults Permanent faults

Drying characteristics, functional properties and in vitro digestion of purple potato slices dried by different methods

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Journal of Integrative Agriculture 2019年第9期18卷 2162-2172页

作者： qiu Gan JIANG Yong-li deng Yun Department of Food Science and Technology Shanghai Jiao Tong University

The drying characteristics,physico-chemical and functional properties,as well as starch digestibility,of purple potato slices dried using different methods(such as,vacuum freeze-drying,VFD;hot-air drying,HAD;air-impingement jet drying,AIJD;and far-infrared assisted heat-pump drying,FIHPD)were *** rate was the highest(3.0 g 100 g^-1 min^-1)using AIJD,followed by FIHPD and HAD,and the rate of VFD was the lowest one(0.3 g 100 g^-1 min^-1).Drying data were fitted to 12 thin-layer drying models,with the Midilli model giving the best ***,AIJD showed higher diffusivity(5.5×10^-10 m^2 s^–1)and energy efficiency(55 J g^-1)than any other drying method used in this *** reference to the samples dried by VFD,the starch granules of the samples obtained by HAD,FIHPD,and AIJD exhibited different extent of disruption,which significantly increased their water absorption capacity,swelling power,and in vitro digestibility,but decreased the peak *** sample resulting from AIJD had the greatest water absorption capacity(7.9 g g^-1)and solubility(21.6%),but the smallest syneresis rate(48%).Good correlation coefficients(R^2>0.98)implied that the pseudofirst order kinetic model adequately described the rate and extent of starch digestion of dried potato *** from AIJD and FIHPD showed the highest digestibility percentages,reaching to 72.4 and 72.5%.Based on the drying rate,specific energy consumption,functional properties and digestibility,AIJD appeared to be quite effective and suitable to be transferred on the industry scale.

关键词： purple potato air-impingement jet drying(AIJD) drying characteristics flour properties starch digestibility

In-situ Observation of Point Defect and Precipitate Evolvement of CLAM Steel under Electron Irradiation

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Journal of Materials Science & Technology 2013年第5期29卷 467-470页

作者： Yong Xin Tongda Ma Xin ju Jie qiu Department of Physics University of Science and Technology Beijing General Research Institute for Nonferrous Metals Institute of Nuclear and New Energy Technology Tsinghua University

The point defect and precipitate evolution of China low activation martensitic steel （CLAM） under electron beam irradiation were characterized by high voltage electron microscopy. The process was recorded in-situ on electronsensitive films. The irradiation dose rate was 1.78 × 10-3 dpa/s and the highest dose was 2.12 dpa/s. Irradiation introduced dislocation loops into the sub-grain, which increased density when the irradiation dose was increased from 0.53 dpa to 1.59 dpa at 723 K. The precipitate, found to be an M6C type, was irradiated at 773 K at the [011] plane direction. The precipitate morphology and structure were unchanged when the irradiation dose was increased to 2.12 dpa. Compared with the irradiation at 723 K in the sub-grain, no other defects were generated at the nearby grain boundary at 773 K.

关键词： Martensitic steel Electron microscopy Electron irradiation Defect Precipitate

Study on concentration and turbulence of solid-liquid FAE in dispersal process

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Defence Technology（防务技术） 2018年第6期14卷 657-660页

作者： Jia-chen Chen Xin Ma qiu-ju Ma China Zhongyuan Engineering Corporation Beijing 100191China China Ordnance Society Beijing 100089China College of Resources&Safety Engineering China University of Mining&Technology(Beijing)Beijing 100083China

This paper describes numerical simulation on dispersion of the solid-liquid mixed fuel driven by explosion load. A model used in numerical calculation for dispersion of solid-liquid mixed fuel was established in this study. The concentration and turbulent intensity in the multiphase cloud of the solidliquid mixed fuel were obtained by numerical simulation. It was found that the fuel concentration tended to be 0.15 kg/m^3, the turbulence intensity tended to be 7 in 90 ms. The numerical results agree with those measured in the experiment.

关键词： Solid-liquid mixed fuel Concentration Turbulence intensity Numerical simulation