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Measurement of insertion loss for underwater acoustic passive materials with the time reversal technique

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Chinese Journal of Acoustics 2014年第2期33卷 109-120页

作者： YAN Xiaowei li jianlong KONG Xiangdong Institute of System Engineering Research Department of Information Science&Electronic Engineering Zhejiang University

A method using the time reversal（TR） technique to measure the insertion loss（IL） of passive materials is *** the received signals are focused according to the TR theory when there is not a sample between the source and the received ***,the sample is placed near the received array and the TR processing is again employed to realize the focus of the received ***,the IL of the sample is evaluated from these focusing *** the TR processing can focus the energy in spatial domain and time domain,the method can be used to measure acoustic properties of passive materials in a waveguide tank with reflections induced by boundaries or with low source *** samples with the same size of 1.1 m×1.0 m×5 mm are tested in the waveguide *** method is demonstrated by the comparison of the theoretical and the experimental results in the measured frequency range of 1-20 kHz.

关键词： time Measurement of insertion loss for underwater acoustic passive materials with the time reversal technique TR

Magnetic-field-assisted triboelectric nanogenerator for harvesting multi-directional wave energy

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Nano Research 2024年第8期17卷 7144-7152页

作者： Mengru Ding jianlong Wang Da Zhao Hengyu li Xiaojun Cheng Jianming Wen Zhong lin Wang Tinghai Cheng Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China School of Nanoscience and Engineering University of Chinese Academy of SciencesBeijing 100049China Guangzhou Institute of Blue Energy Guangzhou 510555China College of Engineering Zhejiang Normal UniversityJinhua 321004China School of Materials Science and Engineering Georgia Institute of TechnologyAtlantaGA 30332-0245USA

Ocean wave energy is a significant and promising source of renewable ***,the energy harvesting is challenging due to the multi-directional nature of *** paper proposes a magnetic-field-assisted triboelectric nanogenerator(MFATENG)for harvesting multi-directional wave *** incorporating a magnetic field,the planar motion of the pendulum is converted into spatial motion,increasing the triggering of multilayered TENG(M-TENG)and enhancing the output energy of the *** results demonstrate that the output energy of the MFA-TENG is increased by 73%by utilizing the magnetic ***,a spring model based on the origami-structured M-TENG is established to analyze the effect of different equivalent stiffnesses on the performance of the M-TENG,aiming to obtain optimal output *** results showcase the impressive output performance of the M-TENG,generating outputs of 250 V,18μA,and 255 ***,the proposed MFA-TENG effectively harvests multi-directional wave energy under water-wave driven *** study significantly enhances the ability of the MFA-TENG to harvest multi-directional wave energy and presents a promising approach for self-powered marine monitoring in the future.

关键词： triboelectric nanogenerator magnetic-field-assisted spring model multi-directional wave energy

信息化背景下兽医影像学微型视频案例库建设及应用——以新疆农业大学为例

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现代畜牧科技 2024年第4期 159-162页

作者：弓超何晓东李建龙张毅王菊梅郭庆勇新疆农业大学动物医学学院新疆乌鲁木齐830052

目前我国畜牧业正处于转型升级的关键期,新疆是我国传统的畜牧业产区,其对动物医学专业人才的质量和数量需求不断提升。兽医影像学是一门操作性和实践性很强的学科。新疆农业大学动物医学学院针对兽医影像学的教学方法和教学模式等方面... 详细信息

目前我国畜牧业正处于转型升级的关键期,新疆是我国传统的畜牧业产区,其对动物医学专业人才的质量和数量需求不断提升。兽医影像学是一门操作性和实践性很强的学科。新疆农业大学动物医学学院针对兽医影像学的教学方法和教学模式等方面进行教学改革的研究与探索,将临床实际病例设计成微型视频案例库,增强学生学习主动性,提高学生专业能力,提升其创新意识和实践能力。

关键词：信息化背景兽医影像学微型视频案例库建设及应用新疆农业大学

A Bayesian approach to matched field processing in uncertain ocean environments

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Chinese Journal of Acoustics 2008年第4期27卷 358-367页

作者： li jianlong PAN Xiang Department of Information Science & Electronic Engineering Zhejiang University Hangzhou 310027

An approach of Bayesian Matched Field Processing （MFP） was discussed in the uncertain ocean environment. In this approach, uncertainty knowledge is modeled and spatial and temporal data received by the array are fully used. Therefore, a mechanism for MFP is found, which well combines model-based and data-driven methods of uncertain field processing. By theoretical derivation, simulation analysis and the validation of the experimental array data at sea, we find that （1） the basic components of Bayesian matched field processors are the cor- responding sets of Bartlett matched field processor, MVDR （minimum variance distortionless response） matched field processor, etc.; （2） Bayesian MVDR/Bartlett MFP are the weighted sum of the MVDR/Bartlett MFP, where the weighted coefficients are the values of the a posteriori probability; （3） with the uncertain ocean environment, Bayesian MFP can more correctly locate the source than MVDR MFP or Bartlett MFP; （4） Bayesian MFP can better suppress sidelobes of the ambiguity surfaces.

关键词： ocean environments matched field processing Matched Field Processing weighted coefficients weighted sum methods of sets of

肝/脾CT值、受控衰减参数(CAP)和磁共振质子密度脂肪分数(MRI-PDFF)在慢性乙型肝炎脂肪变性患者中的应用价值

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临床肝胆病杂志 2024年第1期40卷 46-51页

作者：鲁景楠李岩松温雅王雄慧屈兆宇李建龙张炜延安大学附属医院影像科陕西延安716000 西安国际医学中心医院核医学科西安710100

目的探讨肝/脾CT值(CTL/S)、受控衰减参数(CAP)和磁共振质子密度脂肪分数(MRI-PDFF)在慢性乙型肝炎(CHB)肝脂肪变性患者中的应用价值。方法回顾性收集2018年10月—2022年12月在延安大学附属医院行肝脏CT、CAP和MRI-PDFF检查的213例CHB... 详细信息

目的探讨肝/脾CT值(CTL/S)、受控衰减参数(CAP)和磁共振质子密度脂肪分数(MRI-PDFF)在慢性乙型肝炎(CHB)肝脂肪变性患者中的应用价值。方法回顾性收集2018年10月—2022年12月在延安大学附属医院行肝脏CT、CAP和MRI-PDFF检查的213例CHB患者的临床资料。根据MRI-PDFF结果,将213例患者分为单纯CHB组(MRI-PDFF<5%,n=111)和CHB合并脂肪变性组(MRI-PDFF≥5%,n=102);其中轻度脂肪变性69例,中度至重度脂肪变性33例。符合正态分布的计量资料组间比较采用成组t检验;不符合正态分布的计量资料组间比较采用Mann-Whitney U检验。绘制Bland-Altman图,评价两位医师测量MRI-PDFF的一致性。采用Spearman相关系数分析CTL/S和MRI-PDFF、CAP和MRI-PDFF的相关性。通过分析受试者工作特征曲线(ROC曲线),计算曲线下面积(AUC),评估CTL/S和CAP对不同程度脂肪变性的诊断价值,并使用DeLong检验比较两种影像诊断方法的AUC。结果MRI-PDFF在CHB患者中具有较高的可重复性及稳定性,CTL/S和MRI-PDFF之间呈显著负相关(r=-0.800,P<0.001),CAP与MRI-PDFF之间呈显著正相关(r=0.692,P<0.001)。CTL/S和CAP诊断CHB肝脂肪变性均有较高的准确度(AUC分别为0.951、0.902),且CTL/S优于CAP(P<0.05)。在检测轻度和中重度脂肪变性时,CTL/S的AUC分别为0.921和0.895,CAP的AUC分别为0.859和0.825。结论MRI-PDFF技术在CHB患者中具有较高的可重复性及稳定性,CTL/S和CAP对不同程度的CHB肝脂肪变性均具有较高的诊断价值。

关键词：乙型肝炎慢性脂肪肝诊断

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穿刺活检及联合检测提高脊柱感染病原学诊断的准确性

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骨科 2024年第3期15卷 200-205页

作者：许良孙建民杨永瑞阮文凯李建龙党荣潘谭洪栋山东省公共卫生临床中心脊柱感染外科济南250100 山东省立医院脊柱外科济南250000

目的探讨穿刺活检及联合检测在脊柱感染病原学诊断中的应用价值。方法选取2022年8月至2023年8月山东省公共卫生临床中心脊柱感染外科收治的287例疑似脊柱感染病人,行“C”型臂X线机引导下的穿刺活检,组织标本送联合检测(培养、涂片、基... 详细信息

目的探讨穿刺活检及联合检测在脊柱感染病原学诊断中的应用价值。方法选取2022年8月至2023年8月山东省公共卫生临床中心脊柱感染外科收治的287例疑似脊柱感染病人,行“C”型臂X线机引导下的穿刺活检,组织标本送联合检测(培养、涂片、基因和病理检查)。以临床结果为金标准,计算并对比单纯培养和联合检测的敏感度、特异度、阳性预测值和阴性预测值,绘制ROC曲线,计算曲线下面积(AUC)。结果287次活检均穿刺顺利,包含238份椎间盘标本,49份椎骨标本。临床病原学结果:结核分枝杆菌54例,布鲁氏菌59例,一般细菌153例,非结核分枝杆菌5例、真菌3例;联合检测与单纯培养的敏感度分别为92.17%、58.15%,特异度分别为95.56%、91.65%,阳性预测值分别为98.77%、96.32%,阴性预测值分别为51.82%、91.25%。联合检测的敏感度和阴性预测值均高于单纯培养(P<0.05)。联合检测病原学诊断的AUC明显高于单纯培养(0.87 vs.0.58),差异有统计学意义(P<0.05)。结论“C”型臂X线机引导下穿刺活检是脊柱感染明确病原学诊断的重要手段,单纯培养有一定的漏诊率和误诊率,联合检测可提高诊断效率。

关键词：脊柱感染联合检测 C型臂X线机引导穿刺活检病原学诊断

双气相定量CT对轻中度COPD的评估价值研究

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CT理论与应用研究（中英文） 2024年第2期33卷 189-196页

作者：王雄慧潘娟牛媛沈敏阴玮灵李建龙黄晓旗郭佑民延安大学附属医院影像中心陕西延安716000 延安市人民医院老年病科陕西延安716000

目的:通过配准的双气相定量CT对轻中度慢性阻塞性肺疾病(COPD)患者肺气肿定量指标的对比分析,寻找最优肺气肿定量指标。方法:回顾性收集健康体检对照组55例和慢性阻塞性肺疾病全球倡议(GOLD)1级21例,GOLD 2级31例。将CT原始DICOM数据导... 详细信息

目的:通过配准的双气相定量CT对轻中度慢性阻塞性肺疾病(COPD)患者肺气肿定量指标的对比分析,寻找最优肺气肿定量指标。方法:回顾性收集健康体检对照组55例和慢性阻塞性肺疾病全球倡议(GOLD)1级21例,GOLD 2级31例。将CT原始DICOM数据导入“数字肺”分析平台,测定深吸气末LAA%_(-950)和深呼气末LAA%_(-910)。将呼气相与吸气相CT图像配准,根据阈值法计算出肺气肿区域百分比(PRM~(Emph%))、功能性小气道病变区域百分比(PRMfSAD%)和正常区域百分比(PRM~(Normal%))。肺功能指标包括FVC、FEV_1%、FEV_1/FVC。组间一般资料、CT定量指标和肺功能差异采用独立样本t检验、Mann-Whitney U检验或卡方检验,相关性采用Spearman相关分析。绘制受试者工作特征(ROC)曲线分析CT定量参数对轻中度COPD患者肺气肿的诊断效能。结果:轻中度COPD患者与正常对照组间性别、吸烟指数、FEV1%、FEV1/FVC、吸气相LAA%_(-950)、呼气相LAA%_(-910)、PRM~(Emph%)、PRMfSAD%及PRMNormal%差异均有统计学意义。吸气相LAA%_(-950)与FEV1/FVC呈负相关,呼气相LAA%_(-910)、PRM~(Emph%)与FVC、FEV1%、FEV1/FVC均呈负相关。ROC曲线分析结果显示吸气相LAA%_(-950)、呼气相LAA%_(-910)及PRM~(Emph%)曲线下面积分别为0.742、0.861、0.876,其中PRM~(Emph%)指标的曲线下面积最大,对应临界值为9.84%,敏感度76.90%,特异度94.50%。结论:定量CT肺气肿指标吸气相LAA%_(-950)、呼气相LAA%_(-910)及双气相PRM~(Emph%)都能够客观评估轻中度COPD患者的肺气肿情况,其中PRM~(Emph%)是最优评估指标。

关键词：定量CT 计算机辅助图像处理慢性阻塞性肺疾病肺气肿

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Effect of Boundary Layers on Polycrystalline Silicon Chemical Vapor Deposition in a Trichlorosilane and Hydrogen System

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Chinese Journal of Chemical Engineering 2011年第1期19卷 1-9页

作者：张攀王伟文陈光辉李建隆 Institute of Electronmechanical Engineering Qingdao University of Science and Technology Qingdao 266061 China Institute of Chemical Engineering.Qingdao University of Science and Technology Qingdao 266042 China

This paper presents the numerical investigation of the effects of momentum, thermal and species boundary layers on the characteristics of polycrystalline silicon deposition by comparing the deposition rates in three chemical vapor deposition （CVD） reactors. A two-dimensional model for the gas flow, heat transfer, and mass transfer was coupled to the gas-phase reaction and surface reaction mechanism for the deposition of polycrystalline silicon from trichlorosilane （TCS）-hydrogen system. The model was verified by comparing the simulated growth rate with the experimental and numerical data in the open literature. Computed results in the reactors indicate that the deposition characteristics are closely related to the momentum, thermal and mass boundary layer thickness. To yield higher deposition rate, there should be higher concentration of TCS gas on the substrate, and there should also be thinner boundary layer of HCl gas so that HCl gas could be pushed away from the surface of the substrate immediately.

关键词： boundary layer polycrystalline silicon numerical simulation mass diffusion

^(18)F-prostate specific membrane antigen positron emission tomography/computerized tomography for lymph node staging in medium/high risk prostate cancer:A systematic review and meta-analysis

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Chinese Medical Journal 2024年第8期137卷 949-958页

作者： Zhengtong Lv liuqi Song Miao Wang Huimin Hou Haodong li Xuan Wang Jianye Wang jianlong Wang Ming liu Department of Urology Beijing HospitalNational Center of GerontologyInstitute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China Graduate School of Peking Union Medical College and Chinese Academy of Medical Sciences Beijing 100730China Peking University Fifth School of Clinical Medicine Beijing 100730China Peking University China-Japan Friendship School of Clinical Medicine Beijing 100029China

Background:Lymph node staging of prostate cancer(PCa)is important for planning and monitoring of treatment.^(18)F-prostate specific membrane antigen positron emission tomography/computerized tomography(^(18)F-PSMA PET/CT)has several advantages over^(68)Ga-PSMA PET/CT,but its diagnostic value requires further *** meta-analysis focused on establishing the diagnostic utility of^(18)F-PSMA PET/CT for lymph node staging in medium/high-risk ***:We searched the EMBASE,PubMed,Cochrane library,and Web of Science databases from inception to October 1,*** cancer,^(18)F,lymph node,PSMA,and PET/CT were used as search terms and the language was limited to *** additionally performed a manual search using the reference lists of key *** and study characteristics were extracted and the QUADAS-2 tool was employed to evaluate the quality of included ***,specificity,the positive and negative likelihood ratio(PLR and NLR),diagnostic odds ratio(DOR),area under the curve(AUC),and 95%confidence interval(CI)were used to evaluate the diagnostic value of^(18)F-PSMA PET/*** 17 software was employed for calculation and statistical ***:A total of eight diagnostic tests including 734 individual samples and 6346 lymph nodes were included in this *** the patient level,the results of each consolidated summary were as follows:sensitivity of 0.57(95%CI 0.39-0.73),specificity of 0.95(95%CI 0.92-0.97),PLR of 11.2(95%CI 6.6-19.0),NLR of 0.46(95%CI 0.31-0.68),DOR of 25(95%CI 11-54),and AUC of 0.94(95%CI 0.92-0.96).At the lesion level,the results of each consolidated summary were as follows:sensitivity of 0.40(95%CI 0.21-0.62),specificity of 0.99(95%CI 0.95-1.00),PLR of 40.0(95%CI 9.1-176.3),NLR of 0.61(95%CI 0.42-0.87),DOR of 66(95%CI 14-311),and AUC of 0.86(95%CI 0.83-0.89).Conclusions:^(18)F-PSMA PET/CT showed moderate sensitivity but high specificity in lymph node staging of medium/high-risk *** diag

关键词： ^(18)F-PSMA PET/CT Diagnostic test Lymph node Meta-analysis Prostate cancer