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Analytical expression for betatron tune shift due to field errors in lump quadrupole

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Nuclear Science and Techniques 2016年第1期27卷 5-7页

作者： yuan Chen Cheng-hui yu Qing Qin Jiu-QingWang Shou-Xian fang Institute of High Energy Physics Chinese Academy of Sciences

The integrated gradient of a quadrupole will be deviated by a close neighboring sextupole, and this is called the effect of fringe field interference. Using the Lie algebra techniques, an analytical expression for the betatron tune shift due to this effect has been derived. The process does not depend on the supposition of the thin-lens quadrupoles. It can be used to estimate the tune shift differences between the designed lattice and the one including the fringe field interference. More generally, the method can be applied to other kinds of fringe field interference.

关键词：解析表达式四极杆场误差电场干扰李代数方法 Tron 薄透镜密相

从三例胰岛素瘤诊治经过浅析急诊低血糖的病因鉴别诊断

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临床误诊误治 2017年第1期30卷 38-41页

作者：刘姗姗闫志峰张嘉芳宋菲林芳玉张慧闫鸿解放军202医院急诊科沈阳110003

目的探讨胰岛素瘤的临床特点和低血糖的病因鉴别诊断要点,以降低误诊率。方法对3例胰岛素瘤临床资料进行回顾性分析。结果本组例1以突发意识障碍入院;例2以反复发作性低血糖1年余,意识障碍再发1 h入院;例3以反复心悸、大汗、肢颤1年余,... 详细信息

目的探讨胰岛素瘤的临床特点和低血糖的病因鉴别诊断要点,以降低误诊率。方法对3例胰岛素瘤临床资料进行回顾性分析。结果本组例1以突发意识障碍入院;例2以反复发作性低血糖1年余,意识障碍再发1 h入院;例3以反复心悸、大汗、肢颤1年余,再发10 min入院。3例入院后即刻血糖0.9~2.0 mmol/L,急诊首诊低血糖症。例1经积极救治后,血糖仍持续偏低,家属到达后提供胰岛素瘤病史。例2追问病史获知胰岛素瘤病史。例3经补糖治疗后血糖恢复正常,完善相关检查后证实胰岛素瘤。例1因顽固性低血糖,家属放弃治疗后死亡;余2例转上级医院手术治疗。结论引起低血糖的常见原因是糖尿病,但少见病因如胰岛素瘤也不容忽视。对急诊低血糖患者要在积极救治的同时,注意查找导致低血糖的根本原因。

关键词：胰岛素瘤急诊室医院误诊低血糖症

术前CT无淋巴结转移的右半结肠癌D_3手术198例报告

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中国医刊 2017年第8期52卷 42-46页

作者：李嘉曹锋李昂方育王晓辉刘殿刚李非首都医科大学宣武医院普通外科北京100053

目的探讨D_3手术在术前CT诊断无淋巴结转移的右半结肠癌根治中的价值。方法回顾性分析本院2006年1月至2014年12月手术切除的结肠癌患者的临床资料。CT诊断淋巴结转移的标准为淋巴结短径/长径>0.8,呈圆形或不规则形或呈融合状,增强扫描... 详细信息

目的探讨D_3手术在术前CT诊断无淋巴结转移的右半结肠癌根治中的价值。方法回顾性分析本院2006年1月至2014年12月手术切除的结肠癌患者的临床资料。CT诊断淋巴结转移的标准为淋巴结短径/长径>0.8,呈圆形或不规则形或呈融合状,增强扫描后呈不规则强化。右半结肠癌的D_3清扫定义为清除回结肠动脉、右结肠动脉(若存在)、中结肠动脉右支或主干(扩大右半结肠切除)根部的淋巴结。结果 2006年1月至2014年12月共收治结肠癌患者1278例,275例术前诊断为无淋巴结转移的右半结肠癌患者进入研究。275例患者中分别有77例及198例接受D_2及D_3手术,D_3手术组主淋巴结转移率为3.5%(7/198)。全组患者共有15.6%(43/275)出现术后并发症,其中D_2及D_3组并发症发生率分别为13.0%(10/77)及16.7%(33/198),两组比较差异无显著性。Logistic回归分析发现,高龄、急诊手术、开腹手术及肿瘤高T分期是患者发生术后并发症的危险因素(P<0.05)。结论术前诊断无淋巴结转移的右半结肠癌患者,虽然D_3手术不增加术后并发症的风险,但其主淋巴结实际转移率较低,对患者预后的影响仍待进一步研究。

关键词：结肠癌淋巴结清扫 D3手术

MC-ICP-MS 测定岩石标准物质的钒同位素组成

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岩矿测试 2025年第1期44卷 63-74页

作者：徐丽怡于慧敏丁昕黄方中国科学技术大学地球和空间科学学院岩石圈演化与环境演变全国重点实验室安徽合肥230026 中国科学院比较行星学卓越创新中心中国科学技术大学安徽合肥230026

随着分析方法的发展和分析精度的提升,钒同位素已经越来越多地被用于各种地质过程研究。为了确保钒同位素分析测试过程中,可以有效地监控数据的准确度和精度,方便国际各实验室之间的数据对比,同时考虑到早期国际上常用美国地质调查局(US... 详细信息

随着分析方法的发展和分析精度的提升,钒同位素已经越来越多地被用于各种地质过程研究。为了确保钒同位素分析测试过程中,可以有效地监控数据的准确度和精度,方便国际各实验室之间的数据对比,同时考虑到早期国际上常用美国地质调查局(USGS)的标准物质面临着库存不足等问题,本文采用多接收电感耦合等离子体质谱仪(MC-ICP-MS)测定了一系列国际地质标准物质和国家地质标准物质的钒同位素组成,δ51V值的测试精度优于0.08‰。本文选取的标准物质主要来自日本地质调查局(GSJ)和中国地质科学院地球物理地球化学勘查研究所(IGGE),包括一个安山岩(JA-1),三个玄武岩(JB-3、JB-1b和GBW07105),一个辉长岩(JGb-1),一个辉绿岩(GBW07123)以及一个土壤(GBW07454),钒含量范围为77~635μg/g,涵盖了目前大部分火成岩和部分土壤等天然样品含量的范围。这些标准物质除了土壤GBW07454,其他标准物质的钒同位素组成未曾被报道。经测量表明,辉长岩标准物质JGb-1具有最高δ51V值,为−1.05‰±0.08‰,安山岩标准物质JA-1具有最低δ51V值,为−0.34‰±0.06‰,其余标准物质的δ51V值变化范围为−0.72‰~−0.81‰,均落在MORB范围内。本文对这些标准物质钒同位素组成的报道,丰富了钒同位素研究的标准物质数据库,有助于未来在更多领域开展钒同位素研究。

关键词：钒同位素火成岩 MC-ICP-MS 标准物质高精度分析方法

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Tritium concentration in soybean plants exposed to atmospheric HTO during nighttime and daytime

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Nuclear Science and Techniques 2016年第2期27卷 44-51页

作者： hui-fang Shen Wei Liu College of Arts and Sciences Shanxi Agricultural University Shanghai Institute of Applied Physics Chinese Academy of Sciences

Potted soybean plants were exposed to evaporate HTO for 1 h inside an exposure box at two different growth stage(flowering and podding stage, filling stage)during nighttime and daytime. The concentration of tissuefree water tritium(TFWT) and organically bound tritium(OBT) in leaves and beans was measured at the end of the exposure. The results indicated that the quasi-equilibrium between the TFWT concentrations in the soybean leaves and the HTO concentration of the ambient air moisture required more than 1 h to be reached. The relative TFWT concentrations in the nighttime represent about 1/2 to 2/3of the concentrations obtained in the day in the leaves compared to about 1/2 to 4/3 in the beans. The relative OBT concentrations under night conditions were about 2/5 to 1/2 of those under day conditions in the leaves, contrary to 1/2–7/10 for the beans. By developing tritium concentration assessment model with a short-term release of atmospheric HTO, we comprehensively considered the plant growth stage and the environmental conditions.

关键词：大豆叶片氚浓度植物大气白天高浓度条件游离水评价模型

Experimental investigation on rainfall infiltration and solute transport in layered porous and fractured media

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Journal of Coal Science & Engineering(China) 2012年第1期18卷 29-34页

作者： hui-fang Wang Ming-yu Wang Center for Water System Security & Key Laboratory of Computational Geodynamics Graduate University of Chinese Academy of Sciences Beijing China

Layered structures with upper porous and lower fractured media are widely distributed in the world. An experimen- tal investigation on rainfall infiltration and solute transport in such layered structures can provide the necessary foundation for effectively preventing and forecasting water bursting in mines, controlling contamination of mine water, and accomplishing ecological restoration of mining areas. A typical physical model of the layered structures with porous and fractured media was created in this study. Then rainfall infiltration experiments were conducted after salt solution was sprayed on the surface of the layered structure. The volumetric water content and concentration of chlorine ions at different specified positions along the profile of the experiment system were measured in real-time. The experimental results showed that the lower fractured media, with a considerably higher permeability than that of the upper porous media, had significant effects on preventing water infil- tration. Moreover, although the porous media were homogeneous statistically in the whole domain, spatial variations in the features of effluent concentrations with regards to time, or so called breakthrough curves, at various sampling points located at the horizontal plane in the porous media near the porous-fractured interface were observed, indicating the diversity of solute transport at small scales. Furthermore, the breakthrough curves of the outflow at the bottom, located beneath the underlying fractured rock, were able to capture and integrate features of the breakthrough curves of both the upper porous and fractured media, which exhibited multiple peaks, while the peak values were reduced one by one with time.

关键词： rainfall infiltration solute transport layered porous and fractured media lab experiment breakthrough curves

A theoretical method to characterize the resistance effects of nonflat terrain on wind fields in a parametric wind field model for tropical cyclones

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Tropical Cyclone Research and Review 2024年第3期13卷 161-174页

作者： Gengjiao Ye Pingzhi fang hui yu Shanghai Typhoon Institute of China Meteorological Administration ShanghaiChina Key Laboratory of Numerical Modeling for Tropical Cyclone/CMA ShanghaiChina School of Geography Sciences East China Normal UniversityShanghaiChina Asia-Pacific Typhoon Collaborative Research Center ShanghaiChina

Traditionally,an empirical speed-up factor was introduced to reflect the effects of nonflat terrain on near-surface wind *** this paper,the resistance effects of nonflat terrain are considered by introducing the terrain drag coefficient in the parametric wind field model for tropical cyclones(TCs)with a theoretical *** effects on wind fields are investigated in complex areas along the coastal zone in China under TC *** results show that the terrain drag coefficient is the function of the slope angle and is sensitive to the spatial *** including the resistance effect of nonflat terrain,the TC intensities weaken overall during landfall,with a slight enhancement near the coastal *** wind speeds outside the radius of the maximum wind speed decrease,while the wind speeds within the radius of the maximum wind speed *** the TC eye and the radius of maximum wind speed shrink,which is more obvious when the TC center is entirely over *** a result,the location and magnitude of the maximum wind speed are affected by the nonflat *** changed structure of the wind fields demonstrates the necessity of considering the effects of nonflat terrain in simulating the wind fields under TC conditions.

关键词： Parametric wind field model Tropical cyclones Nonflat terrain Slope angle Terrain drag coefficient Pressure coefficient

基于改进ResNet的多标签胸部X光图像分类

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山东理工大学学报（自然科学版） 2025年第2期39卷 1-9页

作者：方燕燕陈辉安徽理工大学计算机科学与工程学院安徽淮南232001

针对目前胸部X光图像分类方法存在X光特异性特征表达不充分、高频图像特征提取效果差、疾病样本数量不平衡等问题,提出一种基于改进ResNet的多标签胸部X光图像分类方法(multi-label chest X-ray image classification based on improved... 详细信息

针对目前胸部X光图像分类方法存在X光特异性特征表达不充分、高频图像特征提取效果差、疾病样本数量不平衡等问题,提出一种基于改进ResNet的多标签胸部X光图像分类方法(multi-label chest X-ray image classification based on improved ResNet, MLC-ResNet)。首先,设计一个多尺度特征提取和融合模块,以获取更丰富的特征信息;其次,将八度卷积替换为残差结构中的普通卷积,解决X光特异性特征表达不充分问题;再次,为改善高频特征提取效果,在ResNet中引入改进后的多层感知器(multilayer perception, MLP),更好地揭示图像的细节和整体结构,增加分类性能;最后,使用加权交叉熵损失函数增加样本数较少的类别权重,改善样本分布不平衡问题。在ChestX-Ray14和CheXpert数据集上进行实验测试,其平均AUC分别是0.858 7和0.844 7,相较于ResNet分类算法分别提高了4.47%和3.20%。通过与现有方法的对比实验,进一步证明MLC-ResNet模型具有更好的性能。

关键词：多层感知器 ResNet 加权交叉熵损失函数胸部X光图像

广西某高速公路沥青路面车辙病害影响因素分析

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山西建筑 2025年第3期51卷 104-107页

作者：韦明余芳广西交通职业技术学院广西南宁530023

对实体依托工程的现场调研、室内试验和建立模型进行分析,从重载交通、路面结构、抗压强度、压实度等因素分析了对广西高速公路沥青路面车辙病害的影响,提出加强对重载、超载的管制,进行针对性路面结构设计,提高沥青路面施工质量稳定性... 详细信息

对实体依托工程的现场调研、室内试验和建立模型进行分析,从重载交通、路面结构、抗压强度、压实度等因素分析了对广西高速公路沥青路面车辙病害的影响,提出加强对重载、超载的管制,进行针对性路面结构设计,提高沥青路面施工质量稳定性的对策建议。

关键词：沥青路面车辙重载交通路面结构设计抗压强度压实度