检索结果-南通市图书馆

Study on creep deformation and energy development of underground surrounding rock under four‐dimensional support

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Deep Underground Science and Engineering 2024年第1期3卷 25-38页

作者： zhanguo Ma Junyu sun Peng Gong Pengfei Yan Nan Cui Ruichong Zhang School of Mechanics and Civil Engineering China University of Mining and TechnologyXuzhouChina State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering China University of Mining and TechnologyXuzhouChina Department of Mining Engineering Colorado School of MinesGoldenUSA

There is an urgent need to develop optimal solutions for deformation control of deep high‐stress roadways,one of the critical problems in underground *** previously proposed four‐dimensional support(hereinafter 4D support),as a new support technology,can set the roadway surrounding rock under three‐dimensional pressure in the new balanced structure,and prevent instability of surrounding rock in underground ***,the influence of roadway depth and creep deformation on the surrounding rock supported by 4D support is still *** study investigated the influence of roadway depth and creep deformation time on the instability of surrounding rock by analyzing the energy *** elastic strain energy was analyzed using the program redeveloped in *** numerical simulation results indicate that the combined support mode of 4D roof supports and conventional side supports is highly applicable to the stability control of surrounding rock with a roadway depth exceeding 520 *** the increase of roadway depth,4D support can effectively restrain the area and depth of plastic deformation in the surrounding ***,4D support limits the accumulation range and rate of elastic strain energy as the creep deformation time increases.4D support can effectively reduce the plastic deformation of roadway surrounding rock and maintain the stability for a long deformation period of 6 *** confirmed by in situ monitoring results,4D support is more effective for the long‐term stability control of surrounding rock than conventional support.

关键词： coal mines elastic strain energy four‐dimensional support large roadway depth long‐term stability control plastic deformation surrounding rock

Development and validation of a CT-based radiomics model for differentiating pneumonia-like primary pulmonary lymphoma from infectious pneumonia: A multicenter study

在线全文

学校读者我要写书评

暂无评论

Chinese Medical Journal 2023年第10期136卷 1188-1197页

作者： Xinxin Yu Bing Kang Pei Nie Yan Deng Zixin Liu Ning Mao Yahui An Jingxu Xu Chencui Huang Yong Huang Yonggao Zhang Yang Hou Longjiang Zhang zhanguo sun Baosen Zhu Rongchao Shi Shuai Zhang Cong sun Ximing Wang Department of Radiology Shandong Provincial HospitalShandong UniversityJinanShandong 250021China Department of Radiology Shandong Provincial Hospital Affiliated to Shandong First Medical UniversityJinanShandong 250021China Department of Radiology The Affiliated Hospital of Qingdao UniversityQingdaoShandong 266000China Department of Radiology Qilu HospitalShandong UniversityJinanShandong 250012China Department of Medicine Graduate SchoolKyung Hee UniversitySeoul 446701Republic of Korea Department of Radiology Yantai Yuhuangding HospitalAffiliated Hospital of Qingdao UniversityYantaiShandong 164000China Department of Research Collaboration R&D CenterBeijing Deepwise&League of PHD Technology Co.LtdBeijing 100080China Department of Radiology Shandong Cancer Hospital and InstituteShandong First Medical University and Shandong Academy of Medical SciencesJinanShandong 250117China Department of Radiology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan 450052China Department of Radiology Shengjing Hospital of China Medical UniversityShenyangLiaoning 110004China Department of Medical Imaging Jinling HospitalMedical School of Nanjing UniversityNanjingJiangsu 210002China Department of Radiology Affiliated Hospital of Jining Medical UniversityJiningShandong 272029China

Background:Pneumonia-like primary pulmonary lymphoma(PPL)was commonly misdiagnosed as infectious pneumonia,leading to delayed *** purpose of this study was to establish a computed tomography(CT)-based radiomics model to differentiate pneumonia-like PPL from infectious ***:In this retrospective study,79 patients with pneumonia-like PPL and 176 patients with infectious pneumonia from 12 medical centers were *** from center 1 to center 7 were assigned to the training or validation cohort,and the remaining patients from other centers were used as the external test *** features were extracted from CT images.A three-step procedure was applied for radiomics feature selection and radiomics signature building,including the inter-and intra-class correlation coefficients(ICCs),a one-way analysis of variance(ANOVA),and least absolute shrinkage and selection operator(LASSO).Univariate and multivariate analyses were used to identify the significant clinicoradiological variables and construct a clinical factor *** radiologists reviewed the CT images for the external test *** of the radiomics model,clinical factor model,and each radiologist were assessed by receiver operating characteristic,and area under the curve(AUC)was ***:A total of 144 patients(44 with pneumonia-like PPL and 100 infectious pneumonia)were in the training cohort,38 patients(12 with pneumonia-like PPL and 26 infectious pneumonia)were in the validation cohort,and 73 patients(23 with pneumonia-like PPL and 50 infectious pneumonia)were in the external test ***-three radiomics features were selected to build the radiomics model,which yielded AUCs of 0.95(95%confidence interval[CI]:0.94-0.99),0.93(95%CI:0.85-0.98),and 0.94(95%CI:0.87-0.99)in the training,validation,and external test cohort,*** AUCs for the two readers and clinical factor model were 0.74(95%CI:0.63-0.83),0.72(95%CI:0.62-0.82),and 0.73(95%CI:0.62-0.

关键词： Primary pulmonary lymphoma Pneumonia Computed tomography Radiomics Differentiation

基于CT影像特征构建鉴别胃神经鞘瘤与胃间质瘤的列线图模型

在线全文

学校读者我要写书评

暂无评论

中国医师进修杂志 2024年第7期47卷 624-630页

作者：赵鲁平陆浩然王玉红徐景景孙占国陈月芹翁泽灿毛森济宁医学院附属医院医学影像科济宁272000 济宁医学院附属医院肝胆外科济宁2272000 广东省人民医院放射科广东省医学科学院广州510080 济宁医学院附属医院超声医学科济宁272000

目的探讨基于CT影像特征构建术前鉴别诊断胃神经鞘瘤(GS)与胃间质瘤(GST)(长径2~5 cm)的列线图模型。方法回顾性分析2009年7月至2023年4月济宁医学院附属医院和2017年6月至2022年9月广东省人民医院49例GS患者和240例GST患者的临床和影... 详细信息

目的探讨基于CT影像特征构建术前鉴别诊断胃神经鞘瘤(GS)与胃间质瘤(GST)(长径2~5 cm)的列线图模型。方法回顾性分析2009年7月至2023年4月济宁医学院附属医院和2017年6月至2022年9月广东省人民医院49例GS患者和240例GST患者的临床和影像资料。采用多因素Logistic回归分析鉴别GS与GST的独立因素。采用R4.3.1软件构建鉴别GS和GST的列线图模型,绘制受试者工作特征(ROC)曲线,评估列线图模型鉴别GS与GST的效能;通过校准曲线和决策曲线评估列线图模型的预测效能和临床应用价值。结果GS患者和GST患者有临床症状率、钙化率、溃疡率、肿瘤血管率、长短径比值和动脉期与平扫CT值差值(CTV A-N)比较差异无统计学意义(P>0.05)。GS患者女性比例、发生于胃中下部率、混合或腔外型生长率、肿瘤相关淋巴结率、明显强化率、静脉期与平扫CT值差值(CTV P-N)、延迟期与平扫CT值差值(CTV D-N)、静脉期与动脉期CT值差值(CTV P-A)和延迟期与静脉期CT值差值(CTV D-P)明显高于GST患者[75.51%(37/49)比58.33%(140/240)、85.71%(42/49)比54.17%(130/240)、75.51%(37/49)比45.00%(108/240)、44.90%(22/49)比5.42%(13/240)、51.02%(25/49)比27.08%(65/240)、32.0(26.0,43.5)HU比29.0(22.0,37.7)HU、(44.59±13.46)HU比(32.94±12.47)HU、20.0(11.5,25.0)HU比10.0(5.0,17.0)HU和9.0(6.0,12.0)HU比4.0(-2.7,7.0)HU],年龄、形态不规则率、囊变率和不均匀强化率明显低于GST患者[(58.12±12.59)岁比(62.05±11.22)岁、16.33%(8/49)比38.33%(92/240)、18.37%(9/49)比51.25%(123/240)和34.69%(17/49)比56.25%(135/240)],差异有统计学意义(P0.03时,列线图模型较"所有患者视为GS"方案或"所有患者视为GST"方案获得更多的净收益。结论基于CT影像特征的列线图模型可用于术前鉴别GS与GST。

关键词：神经鞘瘤胃胃肠道间质肿瘤体层摄影术,螺旋计算机列线图

在线全文

学校读者我要写书评

暂无评论

MRI影像组学在肺癌中的研究进展

磁共振成像 2023年第6期14卷 129-132,150页

作者：尹猛秦文恒孙占国济宁医学院临床医学院济宁272013 济宁医学院附属医院医学影像科济宁272029

肺癌死亡率居恶性肿瘤首位,早期精准诊断并进行临床干预对提高患者生存率至关重要。CT、MRI、正电子发射计算机断层扫描/电子计算机断层扫描等传统影像学检查技术在肺癌临床评估中提供的信息有限,而影像组学能将影像数据转化为特征空间... 详细信息

肺癌死亡率居恶性肿瘤首位,早期精准诊断并进行临床干预对提高患者生存率至关重要。CT、MRI、正电子发射计算机断层扫描/电子计算机断层扫描等传统影像学检查技术在肺癌临床评估中提供的信息有限,而影像组学能将影像数据转化为特征空间数据从而提供更加全面、深层次的信息,现已成为肺癌研究的新兴领域。本文对影像组学进行概述,并就MRI影像组学在肺癌诊断、鉴别诊断、病理亚型分型、基因突变状态预测、淋巴结转移预测及非手术治疗疗效评估的研究进展进行综述,以期为肺癌的精准诊治提供新的影像学参考。

关键词：肺癌影像组学磁共振成像诊断治疗基因突变淋巴结转移疗效评估

在线全文

学校读者我要写书评

暂无评论

磁共振成像在甲状腺结节诊断中的研究进展

磁共振成像 2023年第8期14卷 150-153,181页

作者：王奕文周哲孙占国济宁医学院临床医学院济宁272013 济宁医学院附属医院医学影像科济宁272029

甲状腺结节为临床常见病变,检出率逐年上升,其中恶性结节约占7%~15%,术前精准的无创影像诊断对制订治疗方案至关重要。磁共振成像(magnetic resonance imaging, MRI)软组织分辨率高、无辐射,已逐步被用于甲状腺结节良恶性鉴别、颈部淋... 详细信息

甲状腺结节为临床常见病变,检出率逐年上升,其中恶性结节约占7%~15%,术前精准的无创影像诊断对制订治疗方案至关重要。磁共振成像(magnetic resonance imaging, MRI)软组织分辨率高、无辐射,已逐步被用于甲状腺结节良恶性鉴别、颈部淋巴结转移和甲状腺癌周围组织侵犯的评估。除常规MRI平扫及增强扫描外,多种功能MRI技术如动态对比增强MRI、体素内不相干运动扩散成像、扩散峰度成像及酰胺质子转移加权成像等在甲状腺结节诊断中发挥着越来越重要的作用,同时也面临诸多挑战。本文就MRI序列及成像技术在甲状腺结节诊断中的应用进行综述,重点阐述功能MRI在甲状腺结节中的研究进展,为促进甲状腺磁共振图像质量提高,进一步通过多模态磁共振序列定量、定性诊断甲状腺结节提供新的思路和方向。

关键词：甲状腺癌甲状腺乳头状癌磁共振成像动态增强磁共振成像体素内不相干运动成像扩散峰度成像 T2*定量成像

在线全文

学校读者我要写书评

暂无评论

河北省廊坊市智慧水文实践与探索

中国水利 2022年第11期 54-55页

作者：孙占国河北省廊坊水文勘测研究中心廊坊065000

一、智慧水文理念在信息化迅速发展的大背景下,在云计算、物联网、大数据、移动互联网、人工智能等新一代信息技术的支撑下,水文工作需要通过全面感知、识别、模拟和预测,向数字化、网络化、智能化加速发展,构建立体化、全方位、广覆盖... 详细信息

一、智慧水文理念在信息化迅速发展的大背景下,在云计算、物联网、大数据、移动互联网、人工智能等新一代信息技术的支撑下,水文工作需要通过全面感知、识别、模拟和预测,向数字化、网络化、智能化加速发展,构建立体化、全方位、广覆盖的水文信息服务体系,彰显大水文发展理念。这就要求水文工作者充分利用现代信息技术,建设集水文信息接收、处理、存储、共享于一体的网络平台,实现水文数据采集自动化、信息传输网络化、数据加工整理程序化、成果资料显示输出平台化,形成法规完善、体制健全、站网合理、技术先进、精准高效、信息及时、预报准确、运行可靠、管理科学、服务全面的管理运行服务体系。

关键词：智慧水文数据采集体制机制平台建设廊坊

Development of in situ characterization techniques in molecular beam epitaxy

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2024年第3期45卷 9-32页

作者： Chao Shen Wenkang Zhan Manyang Li Zhenyu sun Jian Tang Zhaofeng Wu Chi Xu Bo Xu Chao Zhao zhanguo Wang Laboratory of Solid State Optoelectronics Information Technology Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 101804China School of Physics Science and Technology Xinjiang UniversityUrumqi 830046China School of New Energy and Electronics Yancheng Teachers UniversityYancheng 224002China Key Laboratory of Optoelectronic Materials and Devices Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

Ex situ characterization techniques in molecular beam epitaxy(MBE)have inherent limitations,such as being prone to sample contamination and unstable surfaces during sample transfer from the MBE *** recent years,the need for improved accuracy and reliability in measurement has driven the increasing adoption of in situ characterization *** techniques,such as reflection high-energy electron diffraction,scanning tunneling microscopy,and X-ray photoelectron spectroscopy,allow direct observation of film growth processes in real time without exposing the sample to air,hence offering insights into the growth mechanisms of epitaxial films with controlled *** combining multiple in situ characterization techniques with MBE,researchers can better understand film growth processes,realizing novel materials with customized properties and extensive *** review aims to overview the benefits and achievements of in situ characterization techniques in MBE and their applications for material science *** addition,through further analysis of these techniques regarding their challenges and potential solutions,particularly highlighting the assistance of machine learning to correlate in situ characterization with other material information,we hope to provide a guideline for future efforts in the development of novel monitoring and control schemes for MBE growth processes with improved material properties.

关键词： epitaxial growth thin film in situ characterization molecular beam epitaxy(MBE)

体素内不相干运动扩散加权成像在肺部的应用进展

在线全文

学校读者我要写书评

暂无评论

磁共振成像 2022年第2期13卷 141-144页

作者：吕四强秦文恒孙占国济宁医学院临床医学院济宁272013 济宁医学院附属医院医学影像科济宁272029

扩散加权成像(diffusion weighted imaging,DWI)技术无需对比剂即可获得组织的水分子扩散情况。然而单指数DWI无法区分组织内单纯水分子扩散和微循环灌注信息,体素内不相干运动扩散加权成像(intravoxel incoherent motion-diffusion wei... 详细信息

扩散加权成像(diffusion weighted imaging,DWI)技术无需对比剂即可获得组织的水分子扩散情况。然而单指数DWI无法区分组织内单纯水分子扩散和微循环灌注信息,体素内不相干运动扩散加权成像(intravoxel incoherent motion-diffusion weighted imaging,IVIM-DWI)通过双指数曲线拟合,可以分别获得单纯水分子扩散和微循环灌注参数,能够更全面、准确地反映肿瘤组织微观结构的复杂性。近年来,IVIM-DWI在肺部的应用研究逐渐增多,已成为肺功能磁共振成像研究的热点。笔者就肺部IVIM-DWI相关技术参数、IVIM-DWI对肺良恶性病变的鉴别及其在肺癌评估中的应用进展进行综述。

关键词：肺癌体素内不相干运动磁共振成像扩散加权成像

在线全文

学校读者我要写书评

暂无评论

大采高采场上覆岩层运移规律数值模拟

辽宁工程技术大学学报（自然科学版） 2012年第2期31卷 181-184页

作者：孙占国平庄煤业集团有限责任公司内蒙古赤峰024000

为了研究大采高采场上覆岩结构及其运移规律,给大采高工作面的高产高效开采提供理论基础,通过3DEC数值模拟软件,以某矿6.2 m大采高工作面岩层赋存特征为工程背景,分别建立采高为2.2 m,3.2 m,4.2 m,5.2 m,6.2 m时的数学模型,研究不同采... 详细信息

为了研究大采高采场上覆岩结构及其运移规律,给大采高工作面的高产高效开采提供理论基础,通过3DEC数值模拟软件,以某矿6.2 m大采高工作面岩层赋存特征为工程背景,分别建立采高为2.2 m,3.2 m,4.2 m,5.2 m,6.2 m时的数学模型,研究不同采高下的上覆岩层垮落规律.结果表明:采高较低时,随着采高的增加,碎胀系数随着增加,冒落高度也随着增加,但是当采高增加到5.2 m时,随着碎胀系数的增加,冒落高度却几乎不变.采高为2.2 m时,最大离层量为1 m,随采高的增加,离层量基本呈直线增加,当采高大于4.2 m时,离层量增加迅速,当采高增加至6.2 m时,最大离层量可达到3.05m.随着离层量的增加,基本顶失稳时容易给支架造成冲击性载荷,增加动载系数,影响大采高支架的纵向和横向稳定性.

关键词：大采高上覆岩层 3dec 碎胀系数冒落高度离层量支架动载系数