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喀斯特地区多因子生态胁迫问题空间分布——以曲靖市为例

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兰州大学学报（自然科学版） 2024年第3期60卷 379-386页

作者：侯海燕侯至群朱大明昆明理工大学国土资源工程学院昆明650031 昆明市测绘研究院昆明650051

在地理信息技术的支持下,从水土流失、石漠化、地质灾害、生态退化方面对曲靖市生态环境的敏感性进行综合分析.结果表明,曲靖市生态环境不敏感、中度敏感、高度敏感、极度敏感地区分别占研究区总面积的49.44%、 32.51%、 13.96%和4.10%... 详细信息

在地理信息技术的支持下,从水土流失、石漠化、地质灾害、生态退化方面对曲靖市生态环境的敏感性进行综合分析.结果表明,曲靖市生态环境不敏感、中度敏感、高度敏感、极度敏感地区分别占研究区总面积的49.44%、 32.51%、 13.96%和4.10%.不敏感区分布于西南走向;中度敏感区在全市均有分布;高度敏感区和极度敏感区主要分布于曲靖市东部和会泽县西南部.

关键词：生态敏感性喀斯特空间分布

基于InVEST模型的多情景下滇中城市群生境质量时空演变特征及预测

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兰州大学学报（自然科学版） 2024年第4期60卷 547-555页

作者：张露尹朱大明左小清彭秋志宋炜炜昆明理工大学国土资源工程学院昆明650093 昆明理工大学云南省高校高原山区空间信息测绘技术应用工程研究中心云南省自然资源与规划智慧创新实验室昆明650093

对滇中城市群生境质量及影响因素,通过耦合斑块生成土地利用模拟模型和生态系统服务与权衡综合评价模型,模拟不同情景下2030-2050年土地利用变化,探究生境质量的时空演变与空间相关性.结果表明,未来3种情景下,土地利用变化呈现不同趋势... 详细信息

对滇中城市群生境质量及影响因素,通过耦合斑块生成土地利用模拟模型和生态系统服务与权衡综合评价模型,模拟不同情景下2030-2050年土地利用变化,探究生境质量的时空演变与空间相关性.结果表明,未来3种情景下,土地利用变化呈现不同趋势,差异明显;自然发展情景和耕地保护情景下生境质量均值持续降低,生态保护情景生境质量均值上涨,改善效果显著;滇中城市群生境质量在县域空间上存在相关性,生境质量“热点”主要聚集在研究区西部,分布分散且面积不断缩减,“冷点”以经济较为发达的中部地区为核心区域,呈现扩张趋势.

关键词： InVEST模型生境质量多情景模拟滇中城市群

OpenAI背景下测绘工程专业人才培养模式改革与实践

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地矿测绘 2024年第2期40卷 63-66页

作者：李旺陈国平朱大明昆明理工大学国土资源工程学院云南昆明650031

面对人工智能技术的飞速发展,传统学科面临行业转型危机。据此,首先分析了OpenAI背景下测绘工程专业人才培养模式的改革方向。并以昆明理工大学测绘工程系为例,通过对知识体系更新、充实师资力量、跨学科融合和产学融合提出具体改革建议... 详细信息

面对人工智能技术的飞速发展,传统学科面临行业转型危机。据此,首先分析了OpenAI背景下测绘工程专业人才培养模式的改革方向。并以昆明理工大学测绘工程系为例,通过对知识体系更新、充实师资力量、跨学科融合和产学融合提出具体改革建议,评估改革效果,分析存在的问题和未来展望,以期提供经验参考。

关键词： OpenAI 测绘工程专业机器学习人才培养模式

Sulfonated polyetherketone (SPEK-C) films investigated by positron annihilation lifetime spectroscopy and atomic force microscopy

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Nuclear Science and Techniques 2005年第6期16卷 341-346页

作者： YIN Ze-Jie TANG Shi-Biao HUANG Huan zhu da-ming Department of Modern Physics University of Science and Technology of China Hefei 230026 China Department of Physics University of Missouri-Kansas City Kansas City Missouri 64110 USA

The characterization of sulfonated polyetherketone (SPEK-C) films was investigated by using positronannihilation lifetime spectroscopy (PALS) and atomic force microscopy (AFM). It was found that free volume radiusand intensity depend on the variation of sulfonation degree and solvent evaporation time of the films. Pore size anddistribution determined from PALS and AFM measurements showed reasonable agreement.

关键词：原子物理学锰 PALS AFM 显微镜

基于改进DBSCAN省级电力物资仓库聚类的配送车辆路径优化研究

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物流工程与管理 2024年第5期46卷 13-17,55页

作者：蒋正骅高瞻王刘俊朱铭达陈达强国网浙江省电力有限公司温州供电公司物资管理部浙江温州325028 国网浙江省电力有限公司物资管理部浙江杭州310063 国网浙江省电力有限公司嘉兴供电公司物资管理部浙江嘉兴314033 国网浙江省电力有限公司信息通信分公司浙江杭州310016 浙江工商大学管理工程与电子商务学院浙江杭州310018

鉴于电力物资仓库分布点过多且较为分散,其多起点路径配送优化问题比较复杂,文中提出了一种改进DBSCAN聚类算法来简化电力物资多仓库配送车辆路径的两阶段方法。首先,将区域所有仓库进行聚类划分,得到若干个仓库簇,由此将多起点路径配... 详细信息

鉴于电力物资仓库分布点过多且较为分散,其多起点路径配送优化问题比较复杂,文中提出了一种改进DBSCAN聚类算法来简化电力物资多仓库配送车辆路径的两阶段方法。首先,将区域所有仓库进行聚类划分,得到若干个仓库簇,由此将多起点路径配送优化问题转化为多个仓库簇的单起点路径配送优化问题。然后,使用改进C-W法对模型进行求解。最后,以浙江省电力物资仓库作为配送实例,验证了文中所提两阶段方法及算法的可用性和可行性。

关键词：库容均衡改进DBSCAN聚类算法 C-W法路径优化

Astragalus mongholicus ameliorates renal fibrosis by modulating HGF and TGF-β in rats with unilateral ureteral obstruction

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第5期10卷 380-390页

作者： Chuan ZUO Xi-sheng XIE Hong-yu QIU Yao DENG da zhu Jun-ming FAN Department of Nephrology West China Hospital of Sichuan University Chengdu 610041 China

Astragalus mongholicus （AM） derived from the dry root ofAstragalus membranaceus Bge. var. mongolicus （Bge.） Hsiao is a widely used traditional Chinese medicine. The present study investigated the potential role of AM on renal fibrosis on a rat model of unilateral ureteral obstruction （UUO）. We divided 48 Sprague-dawley rats randomly into 4 groups： sham-operated group （Sham）, untreated UUO group, AM-treated （10 g/（kg.d）） UUO group, and losartan-treated （20 mg/（kg.d）） UUO group as positive control. Haematoxylin ＆ eosin （HE） and Masson staining were used to study the dynamic histological changes of the kidneys 7 and 14 d after operation. The expressions of fibronectin （FN）, type I collagen （coil）, hepatocyte growth factor （HGF）, transforming growth factor-β1 （TGF-β1）, and eL-smooth muscle actin （α-SMA） were analyzed by real-time polymerase chain reaction （PCR）, immunohistochemistry staining, and Western blot. Results show that, similar to losartan, AM alleviated the renal damage and decreased the deposition of FN and coil from UUO by reducing the expressions of TGF-β1 and α-SMA （P〈0.05）, whereas HGF increased greatly with AM treatment （P〈0.05）. Our findings reveal that AM could retard the progression of renal fibrosis. The renoprotective effect of AM might be related to inhibition ofmyofibroblast activation, inducing of HGF and reducing of TGF-β1 expression.

关键词： Astragalus mongholicus (AM) Myofibroblast Transforming growth factor-β1 (TGF-β1) Renal interstitial fibrosis,Hepatocyte growth factor (HGF)

Optical Transient Source AT2021lfa:A Possible“Dirty Fireball”

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Research in Astronomy and Astrophysics 2024年第4期24卷 124-133页

作者： Xue-Mei Ye da-ming Wei Yi-ming zhu Zhi-Ping Jin Key Laboratory of dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China National Astronomical Observatories/Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China

AT2021lfa,also known as ZTF21aayokph,was detected by the Zwicky Transient Facility on 2021 May 4,a 05:34:48 ***-up observations were conducted using a range of ground-based optical telescopes,as wel as Swift/XRT and VLA ***2021lfa is classified as an“orphan afterglow”candidate due to its rapid flux decline and its reddened color(g-r=0.17±0.14 mag).For an optical transient source without promp gamma-ray detection,one key point is to determine its burst *** we measure the burst time through fitting the initial bump feature of AT2021lfa and obtain its burst time as 2021 May 3,at 22:09:50 *** afterglowpy,we model the multi-band afterglow of AT2021lfa and find that the standard model canno reproduce the late radio observations *** that the microphysical parameters ε_(e),ε_(B)(the energy fraction given to electrons and magnetic field),andξN(the fraction of accelerated electrons)may vary with time we then model the afterglow of AT2021lfa taking into account the temporal evolution of the physical parameters ε_(e),ε^(B),and ξ_(N) and find in this case the multi-wavelength observations can be reproduced *** initial Lorentz factor of AT2021lfa can be estimated from the peak time of the early afterglow,which yields a value of about 18 suggesting that AT2021lfa should be classified as a“dirty fireball.”From the upper limit for the prompt emission energy of AT2021lfa,we obtain that the radiation efficiency is less than 0.02%,which is much smaller than that of ordinary gamma-ray bursts(GRBs).It is also interesting that the fitted values of jet angle and viewing angle are very large,θ_(c)~0.66 rad,θ_(v)~0.53 rad,which may lead to the low Lorentz factor and radiation *** compared with GRB afterglow samples,it is evident that the onset bump timescale of AT2021lfa satisfies the empirical relationships observed in GRB ***,the luminosity of AT2021lfa falls within the range of observations for GRB samples;howeve

关键词： gamma-rays:ISM methods:numerical radiation mechanisms:non-thermal

Energy deposition of γ-ray in different instances and its influence on energy detection

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Nuclear Science and Techniques 2006年第1期17卷 34-37页

作者： TANG Shi-Biao MA Qing-Li KONG Le YIN Ze-Jie HUANG Huan zhu da-ming Department of Modern Physics University of Science and Technology of China Hefei 230026 China Department of Physics University of Missouri-Kansas City Kansas City Missouri 64110 USA

In this paper, we simulate γ -ray energy deposition for different incident energies with four different mod-els using the tool GEANT4(Geant4.7.0, 2005)developed by CERN (the Center of European Research of Nucleus). The results we obtained indicate that there are different peak values for different incident energies. That is, we can differentiate the incident energy accurately if the detector can determine the peak value accurately. This is meaningful for the geometrical configuration of the detector to get the most probable distribution (MPD) of energy deposition for different incident energies. According to the simulation, we can insert certain slices with large absorption coefficient to obtain a better MPD of energy deposition which will not alter the shape of the energy deposition.

关键词：能量沉积 γ射线能量检测 MPD

Simulation of distribution of radiation energy density in water balls

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Nuclear Science and Techniques 2005年第6期16卷 347-351页

作者： TANG Shi-Biao MA Qing-Li YINZe-Jie TANG Yu HUANG Huan RAO Nan-Xia zhu da-ming Department of Modern Physics University of Science and Technology of China Hefei 230026 China Department of Physics University of Missouri-Kansas City Kansas City Missouri 64110 USA

The distribution of energy deposition density in radiate region and its surrounding areas from γ-rays wassimulated and analyzed for a water-ball model with Geant4 package(Geant4.7.0,2005) developed by CERN (theCenter of European Research of Nucleus). The results show that the distribution depends strongly on the collimatingcondition of radiation beam. A well-collimated beam would reduce radiation effects on surrounding areas.

关键词：放射性能量数值模拟 γ射线计算机模拟波导光学