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Simulation on Sequential Construction Process and Structure of the Pisa Tower
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作者 jun geng Zuping Meng +1 位作者 Bangxun Yin Liufei Zhu 《Journal of Building Construction and Planning Research》 2020年第1期30-41,共12页
The leaning of structures happens all around the world and generates impacts on different extents;thus, it is important to learn about the causes behind. In this report, the sequential construction of a typical leanin... The leaning of structures happens all around the world and generates impacts on different extents;thus, it is important to learn about the causes behind. In this report, the sequential construction of a typical leaning structure, the Tower of Pisa, is discussed and simulated by using a finite element code, PLAXIS. The simulation is performed on a two-dimensional plane with simplifications taken into consideration in making modeling feasible under limitations. Three distinct models are built with one as a control variable, while the other two models are set up with exact eccentricity. Data are obtained from the analysis and are plotted in a graph to clearly show the relationship between the tilting angle and construction phases. With reasonable and completed simulation, the study is able to show the significant role compressible subsoil plays in impacting the tilting performance of a tall building. 展开更多
关键词 The Leaning TOWER of PISA TILTING Angle SEQUENTIAL CONSTRUCTION SUBSOIL TILTING Performance PLAXIS
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Green Prevention and Control Technology of Pests in Cotton Fields in Shandong Province
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作者 Jidi Wang Maode Xing +2 位作者 jun geng Chao Liu Ping Liu 《Plant Diseases and Pests》 CAS 2021年第4期30-32,36,共4页
In order to better serve cotton farmers,green prevention and control technologies of pests are formulated according to the sowing,seedling and adult stages of cotton from the aspects of ecological prevention and contr... In order to better serve cotton farmers,green prevention and control technologies of pests are formulated according to the sowing,seedling and adult stages of cotton from the aspects of ecological prevention and control,physical prevention and control,biological control and scientific use of pesticides,thus realizing green prevention and control of pests during the whole growth period of cotton. 展开更多
关键词 Shandong Province Cotton field PEST Green prevention and control
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Comparative efficacy of oral glucose solution versus non-nutritive sucking for pain relief in neonates during nociceptive procedures: a systematic review
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作者 Hui Liang Xu Tian +5 位作者 Xiao-Ling Liu Yi Dai jun geng Li Kang Zhen Li Li-Fen Jin 《TMR Integrative Nursing》 2018年第3期141-147,共7页
Background and aims: The comparative efficacy of glucose solution (GS) versus non-nutritive sucking (NNS) for pain re- lief in neonate remains controversial. This systematic review was consequently performed to o... Background and aims: The comparative efficacy of glucose solution (GS) versus non-nutritive sucking (NNS) for pain re- lief in neonate remains controversial. This systematic review was consequently performed to objectively investigate the analgesic effect of Oral GS related to NNS in newborns during nociceptive procedures. Methods: All potential records were searched in PubMed, Web of Science, EMBASE, and the Cochrane Library to capture the randomized controlled trials comparing GS with NNS in terms of pain scores in neonates through January 2017. Two independent investigators screened the identified articles, extracted the data, and assessed the methodological quality of the included studies. All statistical analyses were completed by using Review Manager (RevMan) version 5.3.0. Results: Four studies, involving 248 neonates, were incorporated into these statistical analyses. For reducing pain scores, no statistical difference was detected when GS compared to NNS (4 trials; mean difference [MD], 0.75; 95% confidence interval [CI], -0.77 to 2.27; P = 0.33). Conclusion: Both the GS and NNS reduced the pain scores in neonates who undergoing Hepatitis B vaccination and venipuncture, but the NNS is more convenience than GS to some extent. Considered the limited evidences, more randomized controlled trials with high-quality, large-scale and appropriate measures time are warranted to further establish the comparative efficacy of these two options. 展开更多
关键词 NEONATES Oral glucose solution Non-nutritive sucking META-ANALYSIS
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Polyoxometalate-based flexible conductive materials with superionic conductivity
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作者 Yuxin Wang Shuping Xue +7 位作者 jun geng Ying Lu Teng Li Xiaozheng Duan Xue Bai Yanli Yang Jingqi Yang Shuxia Liu 《Science China Chemistry》 SCIE EI CAS CSCD 2024年第10期3299-3309,共11页
Flexible ion-conductive materials exhibit intriguing advantages for applications in flexible electronic devices.Currently,the further enhancement of their conductivity within environmental limitations is an urgent dem... Flexible ion-conductive materials exhibit intriguing advantages for applications in flexible electronic devices.Currently,the further enhancement of their conductivity within environmental limitations is an urgent demand for the development of flexible electronic devices,yet remains as a great challenge.Herein,we report a“dual-acid”strategy,via the encapsulation of two acids,H_(3)PW_(12)O_(40)(HPW) and NH_(2)SO_(3)H(SA),with synergistic interaction into poly(vinyl alcohol)-glycerol(PVA-Gly) hydrogel,to achieve polyoxometalate(POM)-based flexible materials with superionic conductivity under various environmental conditions.As a representative example,the prepared PVA-Gly/HPW-SA-20% hydrogel presents an ultrahigh proton conductivity ranging from -30℃(3.33×10^(-2)S cm^(-1)) to room temperature(2.78×10^(-1)S cm^(-1)) under ambient humidity.Moreover,the PVA-Gly/HPW-SA-20% hydrogel exhibits remarkable advantages in anti-freezing,mechanical flexibility and self-adhesiveness,making it a promising multifunctional electrolyte for flexible electronic devices.Both experimental results and molecular dynamics(MD) simulations jointly demonstrate that SA bridges HPW clusters to form a dense proton transport pathway induced by multiple electrostatic and hydrogen bonding interactions between SA and HPW counterparts,which contributes to the high-level proton conductivity of the PVA-Gly/HPW-SA-20% hydrogel.This work provides new insights into the design of POM-based flexible materials with superionic conductivity. 展开更多
关键词 POLYOXOMETALATES proton conduction dual-acid effect HYDROGEL molecular dynamics simulation
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国内8款常用植物识别软件的识别能力评价 被引量:27
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作者 许展慧 刘诗尧 +23 位作者 赵莹 涂文琴 常诏峰 张恩涛 郭靖 郑迪 耿鋆 顾高营 郭淳鹏 郭璐璐 王静 徐春阳 彭钏 杨腾 崔梦琪 孙伟成 张剑坛 刘皓天 巴超群 王鹤琪 贾竞超 武金洲 肖翠 马克平 《生物多样性》 CAS CSCD 北大核心 2020年第4期524-533,共10页
随着智能手机和人工智能技术的发展,以手机app为载体的植物识别软件慢慢走进公众生活、科普活动和科研活动的各个方面。植物识别app的识别正确率是决定其使用价值和用户体验的关键因素。目前,国内应用市场上有许多植物识别app,它们的开... 随着智能手机和人工智能技术的发展,以手机app为载体的植物识别软件慢慢走进公众生活、科普活动和科研活动的各个方面。植物识别app的识别正确率是决定其使用价值和用户体验的关键因素。目前,国内应用市场上有许多植物识别app,它们的开发目的和应用范围各异,软件本身的关注点、数据库来源、算法、硬件要求也存在很大差异。对于不同人群,植物识别app有不同的意义,如对于科研人员来说,识别能力强的app是提高效率的一大工具;对植物爱好者来说,具一定准确率的识别app可以作为入门的工具。因此,对各app的识别能力进行分析与评价显得尤为重要。本文选取了8款常用的app,分别对400张已准确鉴定的植物图片进行识别,其中干旱半干旱区、温带、热带和亚热带4个区各选取100张。这些图片共计122科164属340种,涵盖了乔木、灌木、草本、草质藤本和木质藤本5种生长型,包含23种国家级保护植物。种、属、科准确识别正确分别计4分、2分、1分,以此标准对软件识别能力按总得分进行排序,正确率得分由高到低依次为花帮主、百度识图、花伴侣、形色、花卉识别、植物识别、发现识花、微软识花。 展开更多
关键词 植物识别软件 花帮主 百度识图 花伴侣 形色 花卉识别 植物识别 发现识花 微软识花
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Evaluation of GOFP over four forest plots using RAMI and UAV measurements 被引量:1
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作者 jun geng Qian Zhang +8 位作者 Feng Qiu J.M.Chen Yongguang Zhang Weiliang Fan Lili Tu Jianwei Huang Shaoteng Wang Lichen Xu Jinchao Li 《International Journal of Digital Earth》 SCIE 2021年第10期1433-1451,共19页
Comparison and validation of canopy reflectance(CR)models are two important steps to ensure their reliability.Pure forest plantations are an ideal type of forest for validating CR models because of their simple backgr... Comparison and validation of canopy reflectance(CR)models are two important steps to ensure their reliability.Pure forest plantations are an ideal type of forest for validating CR models because of their simple background and the low variance in the crown structures which are usually assumed to be identical in most CR models.A Geometric Optical Model for Forest Plantations(GOFP)was compared using dataset in two radiation transfer model intercomparison exercise(RAMI)stands and validated using in situ dataset of detailed optical and structural data of two forest plantations in the Saihanba Forestry Center,China.The results show that(1)the tree distributions in stands described by the hypergeometric model in GOFP show good consistencies with the dataset in the two RAMI stands and measurements from the two Saihanba forest stands;and(2)the CRs simulated with GOFP are also compared well in the two RAMI stands and validated with measurements collected with unmanned aerial vehicles in the two Saihanba stands.GOFP shows a better consistency with the CR measurements than those from CR models for natual forestsbecause the tree distribution in forest plantations is described more reasonably in GOFP. 展开更多
关键词 Validation forest plantation GOFP tree distribution BRF hypergeometric model
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Homogenization of Elliptic Problems with Neumann Boundary Conditions in Non-smooth Domains
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作者 jun geng 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2018年第4期612-628,共17页
We consider a family of second-order elliptic operators {LE } in divergence form with rapidly oscillating and periodic coefficients in Lipschitz and convex domains in Rn. We are able to show that the uniform WI'p es... We consider a family of second-order elliptic operators {LE } in divergence form with rapidly oscillating and periodic coefficients in Lipschitz and convex domains in Rn. We are able to show that the uniform WI'p estimate of second order elliptic systems holds for 2n/n+1-δ〈p〈2n/n-1+δ where δ 〉 0 is independent of ~ and the ranges are sharp for n = 2, 3. And for elliptic equations in Lipschitz domains,the W1,p estimate is true for 3/2 -δ 〈 p〈 3 + δ ifn ≥ 4, similar estimate was extended to domains, the WI'p estimate is true for nconvex domains for 1 〈 p 〈 ∞. 展开更多
关键词 HOMOGENIZATION ELLIPTIC NON-SMOOTH
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