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A fast forward computational method for nuclear measurement using volumetric detection constraints

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Nuclear Science and Techniques 2024年第2期35卷 47-63页

作者： qiong zhang Lin-Lv Lin University of Electronic Science and Technology of China Chengdu 610000China

Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation *** the various detection tools that use nuclear sources,the detector response can reflect various types of information of the *** Monte Carlo method is one of the primary methods used to obtain nuclear detection responses in complex ***,this requires a computational process with extensive random sampling,consumes considerable resources,and does not provide real-time response ***,a novel fast forward computational method(FFCM)for nuclear measurement that uses volumetric detection constraints to rapidly calculate the detector response in various complex environments is ***,the data library required for the FFCM is built by collecting the detection volume,detector counts,and flux sensitivity functions through a Monte Carlo ***,based on perturbation theory and the Rytov approximation,a model for the detector response is derived using the flux sensitivity function method and a one-group diffusion *** environmental perturbation is constrained to optimize the model according to the tool structure and the impact of the formation and borehole within the effective detection ***,the method is applied to a neutron porosity tool for *** various complex simulation environments,the maximum relative error between the calculated porosity results of Monte Carlo and FFCM was 6.80%,with a rootmean-square error of 0.62 *** field well applications,the formation porosity model obtained using FFCM was in good agreement with the model obtained by interpreters,which demonstrates the validity and accuracy of the proposed method.

关键词： Nuclear measurement Fast forward computation Volumetric constraints

Dynamic Characteristic Analysis and Experiment for Integral Impeller Based on Cyclic Symmetry Analysis Method

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Chinese Journal of Aeronautics 2012年第5期25卷 804-810页

作者： WU qiong zhang Yidu zhang Hongwei State Key Laboratory of Virtual Reality Technology and Systems School of Mechanical Engineering and AutomationBeihang UniversityBeijing 100191China

A cyclic symmetry analysis method is proposed for analyzing the dynamic characteristic problems of thin walled integral im- peller. Reliability and feasibility of the present method are investigated by means of simulation and experiment. The fundamental cyclic symmetry equations and the solutions of these equations are derived for the cyclic symmetry structure. The computational efficiency analysis between whole and part is performed. Comparison of results obtained by the finite element analysis （FEA） and experiment shows that the local dynamic characteristic of integral impeller has consistency with the single cyclic symmetry blade. When the integral impeller is constrained and the thin walled blade becomes a concerned object in analysis, the dynamic characteristic of integral impeller can be replaced by the cyclic symmetry blade approximately. Hence, a cyclic symmetry analy- sis method is effectively used to improve efficiency and obtain more information of parameters for dynamic characteristic of integral impellers.

关键词： dynamic characteristic cyclic symmetry impellers simulation finite element analysis blade

Fundamental Characteristics of Tropical Rain Cell Structures as Measured by TRMM PR

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Journal of Meteorological Research 2020年第6期34卷 1129-1150页

作者： Yunfei FU Yilun CHEN Xiangdong zhang Yu WANG Rui LI Qi LIU Lei zhong qiong zhang Aoqi zhang School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China International Arctic Research Center and Department of Atmospheric Sciences University of Alaska FairbanksFairbanksAK 99775USA Department of Physical Geography and Bolin Center for Climate Research Stockholm UniversityStockholm 10691Sweden

Rain cells are the most elementary unit of precipitation system in *** this study,fundamental geometric and physical characteristics of rain cells over tropical land and ocean areas are investigated by using 15-yr measurements of the Tropical Rainfall Measuring Mission(TRMM)Precipitation Radar(PR).The rain cells are identified with a minimum bounding rectangle(MBR)*** results indicate that about 50%of rain cells occur at length of about 20 km and width of 15 *** proportion of rain cells with length>200 km and width>100 km is less than1%.There is a a log-linear relationship between the mean length and width of rain ***,for the same horizontal geometric parameters,rain cells tend to be square horizontally and lanky vertically over land,while vertically squatty over *** rainfall intensity of rain cells varies from 0.4 to 10 mm h-1 over land to 0.4–8 mm h-1 over *** results indicate that the occurrence frequency of rain cells decreases as the areal fraction of convective precipitation in rain cells increases,while such frequency remains almost invariant when the areal fraction of stratiform precipitation varies from 10%to 80%.The relationship between physical and geometric parameters of rain cells shows that the mean rain rate of rain cells is more frequently associated with the increase of their area,with the increasing rate over land greater than that over *** results also illustrate that heavy convective rain rate prefers to occur in larger rain cells over land while heavy stratiform rain rate tends to appear in larger rain cells over *** the same size of rain cells,the areal fraction and the contribution of convective precipitation are about10%–15%higher over land than over ocean.

关键词： rain cell occurrence frequency geometric parameters physical parameters Tropical Rainfall Measuring Mission(TRMM)Precipitation Radar(PR)

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基于乐观阴影集的荧光分子断层成像优化策略

郑州大学学报（理学版） 2025年第1期57卷 40-45页

作者：张钦然国栋凯易黄建谢琼西北大学信息与科学技术学院陕西西安710127 湖南中医药大学第一附属医院湖南长沙410208

荧光分子断层成像(fluorescence molecular tomography,FMT)是一种很有潜力的光学分子影像技术,由于光在生物组织内传输时会产生大量随机的强散射,传播过程极其复杂,使得荧光分子断层成像重建具有高度的病态性。为了获得准确的重建结果... 详细信息

荧光分子断层成像(fluorescence molecular tomography,FMT)是一种很有潜力的光学分子影像技术,由于光在生物组织内传输时会产生大量随机的强散射,传播过程极其复杂,使得荧光分子断层成像重建具有高度的病态性。为了获得准确的重建结果,提出了一种基于乐观阴影集的FMT优化策略。首先,定义了一种基于阴影集的情绪决策—乐观决策和悲观决策。然后,提出了一种基于乐观决策的FMT优化策略,该策略将荧光产额信息转换为模糊信息样本,通过阴影集计算当前模糊信息样本的最佳阈值,对样本的划分采取乐观决策。最后,筛选出荧光目标的预测位置。实验结果表明,所提算法能够有效提高FMT重建的精度。

关键词：阴影集三支决策荧光分子断层成像乐观决策

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New Variable Separation Solutions for Two Nonlinear Evolution Equations in Higher Dimensions

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Chinese Physics Letters 2013年第3期30卷 5-8页

作者： XU Gui-qiong HUANG Xing-zhong Department of Information Management College of ManagementShanghai UniversityShanghai 200444 Department of Mathematics College of SciencesShanghai UniversityShanghai 200444

Based on the multi-linear variable separation approach,a new direct variable separation algorithm is *** effectiveness of the algorithm is demonstrated by the applications of the(2+1)-dimensional modified Korteweg-de Vries equation and the(3+1)-dimensional BKP *** new variable separation solutions which include at least one arbitrary function are derived for these two equations with the aid of Maple.

关键词： equation. separation arbitrary

不同加载速度下巴厘菠萝果皮穿刺力学特性研究

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农机化研究 2025年第3期47卷 169-175页

作者：薛忠潘睿张秀梅中国热带农业科学院南亚热带作物研究所广东湛江524091 中国热带农业科学院农业机械研究所广东湛江524091 农业农村部热带果树生物学重点实验室广东湛江524091

对菠萝果皮穿刺力学特性进行研究,旨在为果实品质评价提供参考,为菠萝采收、加工设备优化改进提供参考,为减轻菠萝果损伤提供理论依据。以巴厘菠萝果皮为研究对象,根据菠萝生长规律将果皮划分为上、中、下3个部位,基于WSW-50E微机控制... 详细信息

对菠萝果皮穿刺力学特性进行研究,旨在为果实品质评价提供参考,为菠萝采收、加工设备优化改进提供参考,为减轻菠萝果损伤提供理论依据。以巴厘菠萝果皮为研究对象,根据菠萝生长规律将果皮划分为上、中、下3个部位,基于WSW-50E微机控制电子万能试验机,选取2、5、10、20、50 mm/min等5个加载速度对菠萝不同部位进行穿刺力学特性试验,分析不同加载速度、不同穿刺部位和不同穿刺压头截面对果皮穿刺强度的影响。试验结果表明:果皮中部穿刺强度最低,下部穿刺强度最高;压头截面与不同穿刺部位对果皮穿刺强度均呈现负相关极显著(p<0.01),不同穿刺部位对果皮穿刺强度均呈现正相关极显著(p<0.01),压头截面与穿刺部位对穿刺强度影响极显著(p<0.01)。由此得出结论:果皮穿刺强度与压头截面、穿刺部位呈极显著相关关系,加载速度与穿刺强度呈不相关关系。

关键词：菠萝果皮加载速度压头截面穿刺强度

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Three-dimensional graphene and its composite for gas sensors

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Rare Metals 2021年第6期40卷 1494-1514页

作者： Meng Hao Wen Zeng Yan-qiong Li zhong-Chang Wang College of Materials Science and Engineering Chongqing UniversityChongqing 400030China School of Electronic and Electrical Engineering Chongqing University of Arts and SciencesChongqing 400030China International Iberian Nanotechnology Laboratory(INL) Avenida Mestre Jose VeigaBraga 4715-330Portugal

As a two-dimensional(2D)material,graphene shows excellent advantages in the field of gas sensors due to its inherent large specific surface area and unique electrical ***,in the practical application of gas detection,graphene sheet is easy to form irreversible agglomeration and has some limitations such as low sensitivity,long response time and slow recovery speed,which greatly reduce its gas sensing *** a gas sensing material,three-dimensional(3D)porous graphene has been extensively studied in recent years owing to its larger specific surface area and stable *** order to synthesize graphene with different three-dimensional structures,many methods have been ***,the synthesis and assembly of three-dimensional graphene and its composites were reviewed,with emphasis on the application of three-dimensional graphene and its composites in the field of gas *** challenges and development prospects of three-dimensional graphene materials in the application of gas sensors were briefly described.

关键词： Three-dimensional graphene Gas sensor Sensitivity Composites material

Evaluation of the Anterior Chamber Angle Structures in Perinatal Infants Using a Wide-Field Digital Fundus Camera

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Current Medical Science 2022年第6期42卷 1305-1309页

作者： Xian zhang Dan-lan LUO Bo CHEN qiong-lei zhong Hong YANG Department of Ophthalmology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China Department of Ophthalmology Hainan General Hospital(Hainan Affiliated Hospital of Hainan Medical University)Haikou570000China

Objective This study aimed to evaluate the ability of a digital fundus camera to observe the development of the anterior chamber angle(ACA)in premature *** Forty-eight eyes of preterm infants(n=48)were examined by a digital fundus camera to observe the development of the *** grading was performed based on the visualization of the anterior chamber structures according to the Scheie Angle Depth Evaluating *** ACA images from all 48 infants were successfully acquired using *** corrected gestational age ranged from 30 weeks to 49 weeks,which covered the period from 2 months preterm to>2 months *** the corrected gestational age increased,the corrected gestational age grading was significantly *** mean corrected gestational ages of the infants corresponding to the ACA classification from grade IV to grade 0 were 32.75±1.89,37.20±1.30,39.75±2.38,40.56±2.24,and 44.23±2.14 weeks,respectively,which were all significantly different(P<0.05).The regression analysis showed a linear correlation between the grading of the ACA and the corrected gestational age(R2=0.724,P=0.0001).Conclusion The ACA of a full-term newborn can be fully detected and evaluated by a digital fundus *** premature infants,part of the ACA is not visible physiologically;however,it should not be misdiagnosed as angle closure or a narrow angle.

关键词： digital fundus camera anterior chamber angle glaucoma infant

Effect of Particle Conductivity on Fe-Si Composite Electrodeposition

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Chemical Research in Chinese Universities 2014年第5期30卷 811-816页

作者： LONG qiong zhong Yunbo ZHENG Tianxiang LIU Chunmei Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai University Shanghai 200072 P R. China

Coatings containing Fe-Si or Si particles were electrodeposited on 3.0%（mass fraction） Si steel sheets. The surface morphology, the cross-section and the silicon content of coating have been investigated, respectively. It was found that the number of particles on the coating surface and cross-section significantly decreased with increasing silicon content in the applied particles, leading to a decrease of the silicon content of coatings. About 10.2% silicon content of coatings deposited with Fe-30%Si particles can be obtained, whereas that for Si particles was only 2.9% at a particle concentration of 100 g/L and current density of 2 A/dm2. This is mainly attributed to the conductivity of applied particles. High conductivity can promote the co-deposition of the particles. With increasing silicon content in the particles, their conductivity decreased sharply, resulting in the decrease of silicon content of coatings. Present work may initiate a new method to modify the particle content of the composite coatings via changing the conductivity of the particles during the composite electrodeposition. In this paper, a possible mechanism was proposed to explain the phenomena.

关键词： Composite electrodeposition Conductivity Fe-Si particle 6.5% Silicon steel